At least one person died following a series of small blasts outside a provincial office of the ruling Communist Party in Shanxi province, northern China, state media report.
The blasts in Taiyuan in Shanxi province appeared to have been caused by home-made bombs, Xinhua reported.
It said eight people had been injured and two cars damaged.
Photos posted on social media showed smoke and several fire engines at the scene of the incident, which happened around 07:40 local time.
No immediate explanation has been given for the incident. There have been occasions in the past where disgruntled citizens have targeted local government institutions.
Tensions are also high in the wake of last week’s incident in Beijing. A car ploughed into a crowd in Tiananmen Square in what the authorities said was a terrorist attack incited by extremists from the western region of Xinjiang.
Later this week, the Communist Party’s top officials will meet in Beijing to start a major economic planning meeting.
“Several small explosive devices went off at Taiyuan’s Yingze Street near the provincial party office,” Shanxi police said in a post on their verified microblog.
“Provincial leaders went to the scene immediately, and police are currently investigating the case,” the post added.
“Police officers found steel balls, circuit boards and similar explosive materials at the scene,” state-run news agency Xinhua said.
“The initial judgement is that the explosions were man-made.”
The explosive devices were hidden in roadside flower beds, according to Chinese state television.
However, two witnesses told Xinhua they saw a minivan exploding, sending car debris flying.
Eyewitnesses also told Xinhua they heard “seven loud blasts”, and saw a large amount of smoke at the site.
Photos posted on microblog Sina Weibo appeared to show cars windows and tyres that were damaged as a result of the blasts, as well as metal ball-bearings.
One of those injured was in a serious condition, state media said.
Taiyuan police said in a verified microblog post that two-way traffic was restored on Yingze Street at 10:30 local time.
Taiyuan, the capital of Shanxi, a province in north central China home to large-scale coal mining, is home to more than four million people.