Syrian PM Wael al-Halqi has survived a car bomb attack targeting his convoy in western Mazzeh district of Damascus, state television said.
There are also reported to be a number of casualties.
UK-based activist group, the Syrian Observatory for Human Rights, said Wael Halqi’s bodyguard had been killed, AFP news agency reported.
The blast is believed to have been a suicide attack.
Syrian PM Wael al-Halqi has survived a car bomb attack targeting his convoy in western Mazzeh district of Damascus
Syrian state television said the explosion happened at a busy intersection. A picture which activists said was of the scene after the attack showed a large plume of black smoke rising into the air near a road and a high-rise building.
Activist groups said a bus and a car had been set on fire.
Mezzeh is a government-controlled quarter housing a military airport which is vital to the regime’s defenses.
Syrian forces and rebels have been fighting around Damascus for months but with neither side gaining an upper hand.
Monday’s attack is the latest bombing inside government-controlled areas.
Late last year there was a suicide bomb attack on the interior ministry. The state media said top officials had escaped unhurt, but it later emerged that the minister himself had been badly injured.
Robert Mood, the former head of the UN observer mission in Syria, says it is “only a matter of time” until President Bashar al-Assad’s government falls.
But Norwegian Maj. Gen. Robert Mood, who left Syria last week, said Bashar al-Assad’s fall would not necessarily mean an end to the 16-month-old conflict.
Syrian forces renewed their assault on the northern city of Aleppo, Syria’s most populous city, on Friday.
The US state department says it fears a massacre by Syrian government forces.
The pro-government al-Watan newspaper warned that the “mother of all battles” was about to start.
“In my opinion it is only a matter of time before a regime that is using such heavy military power and disproportional violence against the civilian population is going to fall,” Maj. Gen. Mood told the Reuters news agency.
Separately, UN High Commissioner for Human Rights Navi Pillay appealed to both sides to spare civilians, citing concerns of “the likelihood of an imminent major confrontation”.
Navi Pillay said she had received “as yet unconfirmed reports of atrocities, including extra-judicial killings and shooting of civilians by snipers” in Damascus.
Saying she had also received more reports of opposition fighters torturing or executing prisoners, Navi Pillay stated her belief that “crimes against humanity and war crimes have been, and continue to be, committed in Syria”.
Robert Mood, the former head of the UN observer mission in Syria, says it is only a matter of time until President Bashar al-Assad's government falls
An activist based in Fardos in Aleppo said at least 15 people had died on Friday morning during the military’s bombardment of a building.
“We have medical supplies but no doctors or equipment to treat the injured. The situation feels hopeless,” said the activist, identified only as Ramy.
“The people of Aleppo are not coping with this crisis. They are dying. It is a massacre. People can leave their homes and move around the city but who would really want to take the risk of being shot or bombed?”
He insisted that activists would continue to resist the government forces.
“Activists are prepared to engage in a guerrilla war, from street to street if necessary,” he said.
The Red Crescent has suspended some of its operations in Aleppo because of the heavy fighting.
Rebels have been stockpiling ammunition and medical supplies in preparation for the expected assault.
Syrian troops fired from helicopter gunships on south-western neighborhoods on Friday morning, the Syrian Observatory for Human Rights told the AFP news agency.
A convoy of tanks from Idlib province, near the border with Turkey, arrived in Aleppo overnight and was attacked by rebels, the Observatory said.
The US State Department said the deployment of tanks, helicopter gunships and fixed-winged aircraft around Aleppo suggested an attack was imminent.
But the US would not intervene, said spokeswoman Victoria Nuland, except by continuing to channel non-lethal assistance (such as communications equipment and medical supplies) to the rebels.
A Syrian MP from Aleppo has fled to Turkey, Turkey’s state-run Anatolia news agency says.
Ikhlas Badawi, a mother of six, said she was defecting in protest at the “violence against the people”.
Meanwhile, another defector, Gen. Manaf Tlas, has put himself forward as a possible figure to unite the fractious opposition.
In an interview with a Saudi newspaper, Asharq al-Awsat, he said: “I am discussing with… people outside Syria to reach a consensus with those inside.”
However, some in the opposition regard Gen. Manaf Tlas – who fled earlier this month – as a compromised figure too close to the government of President Bashar al-Assad.
For its part, Turkey has said it will not tolerate the creation of a Kurdish-run region in northern Syria.
This follows reports that Kurdish rebels in northern Iraq had formed an alliance with a Kurdish party across the border in Syria.
Turkey would strike against “terrorists” in northern Syria, warned Prime Minister Recep Tayyip Erdogan, in the same way it has attacked bases in northern Iraq used by militants linked to the Kurdistan People’s Party (PKK).
Turkey is concerned that the creation of a Kurdish authority in the north of Syria could provide a sanctuary to Kurdish rebels fighting for self-rule in Turkey’s southeast.
Fighting in Syria has become so widespread that the conflict is now in effect a civil war, says The Red Cross (ICRC).
The change in status means combatants will now be officially subject to the Geneva Conventions, leaving them more exposed to war crimes prosecutions.
The Red Cross had previously regarded only the areas around Idlib, Homs and Hama as war zones.
Meanwhile, Syrian officials are disputing claims that they used heavy weapons in fighting on Thursday.
Activists initially described fighting in the village of Tremseh near Hama as a massacre of dozens of civilians, but later accounts suggested most of the dead were armed rebels.
Fighting in Syria has become so widespread that the conflict is now in effect a civil war
The UN accused Syrian forces of using heavy artillery, tanks and helicopters, but Damascus denied those allegations and said just two civilians had been killed.
The accusations, if proved, would mean Damascus had broken an agreement it made with envoy Kofi Annan.
The International Committee of the Red Cross, which oversees the Geneva Conventions, said fighting had now spread beyond the three hotspots of Idlib, Homs and Hama.
Spokesman Hicham Hassan said Syria was now regards as a “non-international armed conflict”, which is the technical term for civil war.
“What matters is that international humanitarian law applies wherever hostilities between government forces and opposition groups are taking place across the country,” he said.
The statement is significant because it is the Red Cross’ job to monitor the conduct of the fighting, and to tell warring parties what their obligations are.
Under the Geneva Conventions, indiscriminate attacks on civilians, attacks on medical personnel or the destruction of basic services like water or electricity are forbidden and can be prosecuted as war crimes.
From now on, all those fighting in Syria are officially subject to the laws of war, and could end up at a war crimes tribunal if they disobey them.
Last month, the UN’s head of peacekeeping Herve Ladsous also said Syria was in a state of civil war.
And Syrian President Bashar al-Assad has previously said the country is in a state of war.
Some 16,000 people are thought to have been killed since the uprising against Bashar al-Assad’s regime began in March 2011.
UN diplomats are attempting to agree a way forward for the organization’s monitoring mission in the country.
The mission’s mandate runs out on Friday, and Western nations are trying to get Russia and China to agree to a beefed-up resolution authorizing sanctions.
About 200 people are reported to have been killed in the Syrian village of Tremseh, in Hama province.
Opposition activists quoted residents as saying the village was attacked with helicopter gunships and tanks.
Pro-government Shabiha militia later went in on foot and carried out execution-style killings, they said.
State media said “terrorist groups” had carried out a massacre to raise tensions ahead of a UN Security Council meeting on the Syria observer mission.
If it is confirmed, the Tremseh attack would be one of the bloodiest single events in the Syria conflict.
Some 16,000 people are thought to have been killed since the uprising against Bashar al-Assad’s regime began in March 2011.
Reports suggest the army was trying to take back Tremseh after it had fallen into rebel hands.
Both sides agreed many people were killed in Tremseh, but have totally different versions of what happened.
About 200 people are reported to have been killed in the Syrian village of Tremseh
Activists say government forces surrounded the village on Thursday morning and heavily bombarded it for several hours, killing many people.
Pro-government militias from nearby Alawite villages then moved in, they said, killing many more villagers and setting fire to houses. Others who tried to flee through fields were also gunned down, the activists said.
State media said gunmen from what they termed armed terrorist groups had attacked the village in the morning, shooting dead dozens of people.
The Revolution Leadership Council of Hama told the Reuters news agency that most of the dead in Tremseh were civilians. Protests condemning the attack have been reported in Damascus, Idlib and Hama.
Earlier on Thursday, Syria’s ambassador to Iraq Nawaf al-Fares announced his defection, following in the footsteps of a former senior general who escaped the country earlier this week.
Iraqi officials have said Nawaf al-Fares, who has publicly declared his support for the opposition, is in Qatar.
Syrian forces also shelled the suburbs of Damascus later in the day in an apparent offensive against rebel fighters.
Western nations are pressing the UN to threaten Syria with sanctions as it considers renewing the mandate for its observer mission in Syria which expires on 20 July.
They want a 10-day ultimatum to be part of a Security Council resolution on the future of the UN’s observer mission in the country. A new resolution must be passed before the mission’s mandate ends on Friday next week.
China and Russia continue to oppose any moves to threaten Damascus with further sanctions ahead of the 20 July deadline.
The mission had a 90-day remit to monitor a truce, but fighting has continued largely unabated.
The truce formed part of a six-point peace plan brokered by UN-Arab League envoy Kofi Annan, who has called for “clear consequences” for the Syrian government and rebels if the ceasefire is not observed.
Turkish army has scrambled six F-16 fighter jets near its border with Syria after Syrian helicopters came close to the border.
Six jets were sent to the area in response to three such incidents on Saturday, the statement said, adding that there was no violation of Turkish airspace.
Last month, Syrian forces shot down a Turkish jet in the border area.
The incident further strained already tense relations between former allies.
Turkey’s government has been outspoken in its condemnation of Syria’s response to the 16-month anti-government uprising, which has seen more than 30,000 Syrian refugees enter Turkey.
On Friday, Turkey said it had begun deploying rocket launchers and anti-aircraft guns along the border in response to the downing of its F-4 Phantom jet on 22 June.
The move came after Prime Minister Recep Tayyip Erdogan warned that Turkey had changed its rules of military engagement and would now treat any Syrian military approaching the border as a threat.
Turkish army has scrambled six F-16 fighter jets near its border with Syria after Syrian helicopters came close to the border
Syria said the Turkish F-4 was shot down by air defence fire inside its airspace. Turkey insists it was downed by a missile after briefly entering and the leaving Syrian airspace.
The plane crashed in the Mediterranean, off the coast of the southern province of Hatay. Its pilots are still missing.
Recep Tayyip Erdogan spoke of Turkey’s “rage” at the incident and described Syria as a “clear and present threat”.
NATO condemned the attack and voiced strong support for Turkey, after Ankara invoked Article 4 of NATO’s founding treaty, which entitles any member state to ask for consultations if it believes its security is threatened.
Four of the six jets were scrambled on Saturday from the airbase of Incirlik in response to two occasions of Syrian helicopters flying close to Hatay province, Sunday’s army statement said.
Later, two more F-16s took off from a base near Batman, in southeastern Turkey, after Syrian helicopters were spotted close to the province of Mardin, it added.
The military said the helicopters flew as close as 6.5 km (4 miles) to the border, according to the AP news agency.
The border incident comes after the UN and Arab League envoy on Syria, Kofi Annan, warned of the danger of the Syria conflict spilling over into the wider region if the bloodshed is not stopped.
He was addressing an international meeting of major international and regional powers in Geneva on Saturday, aimed at reviving the six-point peace plan for Syria brokered by Kofi Annan.
The countries present at the Geneva talks reached an agreement calling for a ceasefire and a transitional government in Syria.
Western demands to exclude President Bashar al-Assad and his allies from the interim administration reportedly foundered on opposition from Russia.
Moscow sees Syria as its closest ally in the region, and rejects any attempt to impose a solution on Syria from the outside.
The Paris-based opposition Syrian National Council rejected the Geneva deal as too ambiguous, according to the AP news agency.
Violence has worsened in Syria recently despite the cease-fire mediated by Kofi Annan as part of his six-point plan earlier this year.
On Friday, government forces recaptured the Damascus suburb of Douma – an opposition stronghold – after 10 days of artillery bombardment. Activists described conditions in the town as “catastrophic”.
Activists estimate that as many as 15,800 have died since the uprising began early last year. Casualties figures are difficult to verify, as Syria does not allow foreign journalists to operate on its territory.
The conflict is seen as becoming increasingly militarized, with both rebels and government forces thought to be receiving arms supplies from abroad.
Turkey has called a NATO meeting to discuss its response to the shooting down of one of its warplanes by Syrian forces on Friday.
Ankara has invoked Article 4 of NATO’s charter, under which consultations can be requested when an ally feels their security is threatened, officials say.
Earlier, Turkey’s foreign minister said the F-4 Phantom was in international airspace when it was shot down.
Syria has insisted the jet was engaged while it was inside its airspace.
It has also said no act of hostility was intended, noting that as soon as the military discovered the “unidentified” aircraft was Turkish its navy joined efforts to rescue the two crew members.
The Turkish foreign ministry said it knew the coordinates of the jet, which was in Syrian territorial waters at a depth of 1,300 m (4,265 ft), but has not yet found it.
The coast guard is still searching for the crew in the Mediterranean Sea, though hopes are fading of them being found alive.
The government has also issued a diplomatic protest note to Syria.
NATO spokeswoman Oana Lungescu said the North Atlantic Council, the principal political decision-making body within the military alliance, would meet in Brussels on Tuesday to discuss the incident.
“Turkey has requested consultations under Article 4 of NATO’s founding Washington Treaty,” she told Reuters.
“Under article 4, any ally can request consultations whenever, in the opinion of any of them, their territorial integrity, political independence or security is threatened.”
Turkey wants to be sure of the strongest backing once it decides its official response.
Foreign Minister Ahmet Davutoglu became the first senior Turkish official to challenge Syria's account of the downing of the jet
The government has promised that it will be strong, decisive and legitimate, and that it will share all the information it has with the public.
Earlier, Foreign Minister Ahmet Davutoglu became the first senior Turkish official to challenge Syria’s account of the downing of the jet.
After lengthy meetings with military chiefs, he told TRT state television that the unarmed jet had “momentarily” entered Syrian airspace by mistake on Friday but had left when it was shot down 15 minutes later.
“According to our conclusions, our plane was shot down in international airspace, 13 nautical miles (24 km) from Syria,” he said.
According to international law, a country’s airspace extends 12 nautical miles (22.2 km) from its coastline, corresponding with its territorial waters.
Ahmet Davutoglu also insisted that the jet had not been on a “covert mission related to Syria” but had instead been carrying out a training flight to test Turkey’s radar capabilities.
He said the plane had not “shown any hostility”, been clearly marked as Turkish, and that he did not agree with the Syrian military’s statement that it had not known to whom it belonged.
The Turkish military said it lost radio contact with the F-4 Phantom at 11:58 (08:58 GMT) on Friday while it was flying over Hatay province, about 90 minutes after it took off from Erhac airbase in the province of Malatya, to the north-west.
Later, the Syrian military said an “unidentified air target” had penetrated Syrian airspace from the west at 11:40 local time (08:40 GMT), travelling at very low altitude and at high speed.
It said that in line with the laws prevailing in such cases, Syrian air defences engaged the craft, and scored a direct hit about 1 km (0.5 nautical miles) from its coastline.
It burst into flames, and crashed into the sea at a point 10 km (5 nautical miles) from the village of Om al-Tuyour, off the coast of Latakia province, well within Syrian territorial waters, the statement added.
Relations between NATO-member Turkey and Syria, once close allies, have deteriorated sharply since the uprising against Syrian President Bashar al-Assad began in March 2011. More than 30,000 Syrian refugees have fled the violence across the border into Turkey.