Four people have been shot dead after a gunman opened fire in Rancho Tehama, northern California, at several locations, including an elementary school, police have said.
The shooting began at a home in the rural community about 120 miles from Sacramento, on November 14.
Police say the gunman was shot dead by police after four people were killed and 10 others injured in the rampage.
Officials believe the shootings started as a “domestic violence incident”.
Tehama County Assistant Sheriff Phil Johnston told the AP that the gunman tried to enter the Rancho Tehama Elementary School with the intention to shoot more children, but was stopped once staff initiated a lockdown.
School officials heard shots being fired and immediately locked the school down, Phil Johnston said. He added that the decision saved children’s lives.
“The shooter literally took his vehicle and rammed their fence and gate, entered the grounds on foot with a semiautomatic rifle,” he told reporters.
A motive is still unclear, but police said the attacker had been involved in a domestic violence incident a day earlier.
The assailant, who has yet to be identified, appeared to be “randomly picking targets”, Phil Johnston told the Los Angeles Times.
A student at the elementary school was shot and another child was hit in a truck along a road, Phil Johnston said. A woman driving the truck was also struck and all three were being treated for injuries, he said.
One of the four victims was a neighbor the gunman was accused of assaulting in January, the AP reported.
Phil Johnston said the neighbor, a woman, had a restraining order against the gunman.
A semi-automatic rifle and two handguns were recovered from one of the crime scenes, police said.
The Redding Record Searchlight spoke to a man who said he was a neighbor of the unidentified gunman.
Brian Flint said his neighbor “has been shooting a lot of bullets lately, hundreds of rounds, large magazines”.
“We made it aware [to police] that this guy is crazy and he’s been threatening us,” Brian Flint told the publication.
California Governor Jerry Brown issued a statement saying he and his wife were “saddened to hear about today’s violence in Tehama County”.
“We offer our condolences to the families who lost loved ones and unite with all Californians in grief.”
VP Mike Pence tweeted: “Saddened to hear of the shooting in N. California, the loss of life & injuries, including innocent children. We commend the effort of courageous law enforcement. We’ll continue to monitor the situation & provide federal support, as we pray for comfort & healing for all impacted.”
Police have found bomb equipment, weapons and thousands of rounds of ammunition at San Bernardino shooters’ home.
The attackers killed 14 people and wounded 21 at San Bernardino’s Inland Regional Center in California.
Authorities still have not found a motive in the attack by Syed Rizwan Farook, 28, and Tashfeen Malik, 27.
According to police, the attack indicated there had been “some degree of planning”.
San Bernardino Police Chief Jarrod Burguan said it appeared that the duo was prepared to carry out another attack.
“There was obviously a mission here. We know that. We do not know why. We don’t know if this was the intended target or if there was something that triggered him to do this immediately,” said David Bowdich, assistant director of the FBI’s Los Angeles office.
In the shootout with police hours after the attack, Syed Rizwan Farook and Tashfeen Malik fired 76 rounds of ammunition at the officers and the officers fired 380 rounds back.
Two police officers were injured during the pursuit.
San Bernardino attack marks the deadliest mass shooting in the US since 26 people were killed at a school in Newtown, Connecticut in 2012.
Authorities are expected to start releasing the names of the victims on December 3.
President Barack Obama said the FBI had taken over the investigation from local authorities.
“It is possible that this was terrorist-related, but we don’t know. It’s also possible that this was workplace-related,” he said.
“We’re going to have to search ourselves as a society to make sure we can take basic steps that would make it harder – not impossible, but harder – for individuals to get access to weapons.”
Law enforcement officials are also looking at possible “co-conspirators” and have been in touch with the suspects’ relatives.
Syed Rizwan Farook, who was born in the US, was not “on the radar” of law enforcement, Jarrod Burguan said.
He worked for the past five years as a restaurant inspector for the San Bernardino County Health Department. The Los Angeles Times reported that co-workers said he was a devout Muslim but rarely discussed his religion.
He and Tashfeen Malik were recently married and had a six-month-old baby, who they dropped off at its grandmother’s house before the attack.
On December 2, Syed Rizwan Farook and his colleagues were attending a holiday party at the Inland Regional Center.
Co-worker Patrick Baccari said he was sitting at the same table as Syed Farook before he abruptly left, leaving his coat.
Wearing military-style clothing and armed with assault rifles and semi-automatic handguns, Syed Farook returned with Tashfeen Malik a short time later to open fire.
When the shooting started, Patrick Baccari took refuge in a bathroom and was hurt when shrapnel sliced through the wall.
Police have named two suspects killed after a mass shooting in San Bernardino, California, left 14 people dead at a social services center.
The man and woman, Syed Rizwan Farook, 28, and Tashfeen Malik, 27, were killed in an exchange of fire with police.
Syed Rizwan Farook had been a San Bernardino public health employee for five years, police chief Jarrod Burguan said.
The attack took place at an event on December 2 for Syed Rizwan Farook’s colleagues. None of the victims has been identified.
The Inland Regional Center, where the shooting took place, provides services for people with developmental disabilities, but the shooting appeared to be unrelated to its clients.
The incident marks the deadliest mass shooting in the US since 26 people were killed at a school in Newtown, Connecticut in 2012.
Jarrod Burguan, who said another 17 people were wounded, said police were “reasonably confident” that there were just two shooters.
A third person seen running from the scene was detained, but police said it was unclear whether that person was involved.
Both suspects were killed in their vehicle after a shoot-out with police involving 20 officers. A tip-off had earlier led police to a house in nearby Redlands.
The dead man and woman were believed to be a couple, the police chief said. They were armed with assault rifles and semi-automatic handguns and wore military-style clothing.
According to the US Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), two of the four guns recovered were linked to “an individual associated with this investigation”. They are investigating the origin of the other two guns.
One police officer was injured, but his injuries are not life threatening.
Three possible explosive devices were found at the Inland Regional Center, where the shooting took place.
Jarrod Burguan said that Syed Rizwan Farook had left the event – which was possibly a holiday party for employees or a meeting – “under some circumstances that were described as angry,” and returned with Tashfeen Malik.
Earlier, the FBI said it was not ruling out the possibility of terrorism but the situation was still being investigated.
San Bernardino is a city of about 200,000 people, 60 miles east of Los Angeles.
The attack took place in a conference area where the San Bernardino County Department of Public Health was holding a social event, said Maybeth Field, the center’s president.
Syed Rizwan Farook, who was born in the US, worked for the county as an environmental health specialist, police said. They had no information on whether he had a criminal record, nor further details on Tashfeen Malik.
Colleagues told the Los Angeles Times that Syed Rizwan Farook had traveled to Saudi Arabia and returned with a new wife. The couple had a young baby, they said.
His brother-in-law, Farhan Khan, told a press conference he had “absolutely no idea” what could have prompted the shooting.
The mass shooting comes just days after three people were killed at a Colorado Planned Parenthood clinic.
President Barack Obama said in response to San Bernardino shooting: “One thing we do know is that we have a pattern of mass shootings in this country that has no parallel anywhere in the world.
“There are some steps that we could take, not to eliminate all incidents, but to make sure they happen less frequently.”