Chinese police on Friday detained a local thief over deadly blasts that struck near a provincial Communist Party headquarters, just over a week after a fiery attack in Beijing's Tiananmen Square that was blamed on Uighur separatists.
The man's capture, reported by state media, comes one day ahead of a highly anticipated meeting of top party leaders in Beijing.
While a potential motive remained unclear, details of the attack suggest anger at the local government could have been behind the bombings.
Protests in China -- on a host of issues including local corruption, land seizures, environmental policy, and labour rights -- are estimated to top 180,000 a year, even as the government devotes vast sums to "stability maintenance".
The apprehended suspect was named as Feng Zhijun, a 41-year-old ex-convict and resident of the city of Taiyuan where the explosions took place, the state-run Xinhua news agency said, citing Shanxi province's Public Security Department.
Feng was captured at 2:00 am Friday (1800 GMT Thursday) and has admitted to the blasts, Xinhua said, which killed one person and wounded eight others Wednesday morning near the party provincial commission in Taiyuan.
Feng previously served nine years in prison for theft, the news agency said.
Police found a "large amount of evidence", including self-made bombs in Feng's car and home in Taiyuan's Xinghualing district, Xinhua said.
Large metal ball bearings and circuit boards were found at the scene of the multiple blasts on Wednesday morning, suggesting the use of home-made devices intended to inflict maximum damage.
The explosions came a little over a week after a fiery attack in Beijing's Tiananmen Square that killed three tourists and wounded dozens at the symbolic heart of the Chinese state.
Beijing described the Tiananmen incident as a "terror attack" carried out by members of the Uighur minority from northwest Xinjiang with links to a separatist group called the East Turkestan Islamic Movement.
By contrast, details of the Taiyuan attack suggest it could have been motivated by local grievances.
The first bomb that went off was detonated near the gate of an office where residents with complaints against the local government can file petitions, according to The Mirror, a Beijing-based newspaper.
The street where the bombs exploded was also the scene of a protest by some 200 laid-off workers last week, according to microblog postings.
Legal paths for pursuing justice in China are limited, as courts are subject to political influence and corruption, and citizens who lodge complaints against authorities often end up in detention.
Disgruntled citizens have staged several incidents elsewhere in the country in recent years.
In June, a street vendor set fire to a bus in Xiamen in east China's Fujian province, killing himself and nearly four dozen passengers in an act of retaliation against local authorities.
One of the highest-profile cases came in July, when Ji Zhongxing, a wheelchair-bound man from southern China, detonated a homemade bomb at Beijing's international airport in a protest against alleged police brutality.
Ji was sentenced last month to six years in jail, a punishment that triggered a wave of public sympathy among users of China's popular online social networks.
Many commenters on China's Twitter-like microblogs, known as weibo, expressed frustration on Friday at the lack of details regarding the suspect's motivation in the Taiyuan explosions, with some filling the void with their own speculation.
"He's already spent nine years in prison. This man is getting revenge on society," wrote one user.
"It's admirable that the police solved the case so quickly, but it's hard to understand why they're so closely guarding information about the suspect's motivation," wrote another. "Why did this person want to cause an explosion? Mustn't he have a reason?"