BEIJING -- An unemployed man intent on killing himself set off an explosion that engulfed a bus in flames and killed 47 people in the southeastern city of Xiamen on Friday, according to reports on Saturday by state-run news organizations.
The reports identified the man as Chen Shuizong, who was about 60 and impoverished. He had written a suicide note in which he expressed deep frustration, said the reports, which were based on details of the investigation released by officials in Xiamen. Mr. Chen was believed to have died in the explosion.
Southern Daily, the official newspaper of Guangdong Province, posted on its microblog a photograph of the man identified as Mr. Chen. He is seen pulling a bag behind him. The picture appeared to have been taken by an overhead security camera in the bus depot or on a street near it.
The state news agency Xinhua said earlier on Saturday that the explosion was believed to be a "serious criminal case." It occurred at 6:20 p.m. Friday, at the height of the rush hour. Ninety people were aboard the bus, which was part of Xiamen's Bus Rapid Transit system. Thirty-four people were hospitalized.
Of those, seven were students. There were 15 students on board the bus, and eight were still unaccounted for, Xinhua reported.
The Xinhua article did not say exactly how the bus explosion was caused. It said that the bus had a diesel engine and that Mr. Chen might have used gasoline. The tires and oil tank of the bus were not damaged before the explosion, Xinhua said.
A photograph accompanying the Xinhua article showed a vehicle in flames on an elevated highway that runs through Xiamen. Dark smoke billowed from the wreckage. The accompanying caption said the explosion occurred near the Jinshan bus stop.
Xiamen is on the southeast coast of China, in Fujian Province, and is considered one of the most livable cities in a country full of congested and polluted urban centers. Many prominent Chinese have worked and lived there at some point in their careers. Xi Jinping, the new leader of the Communist Party, served as Xiamen's vice mayor during his many years climbing the party ladder. Hu Shuli, a well-known journalist who founded Caixin, an investigative magazine, worked there for a state-run newspaper.
In 1999, a corruption scandal involving many politicians and businessmen was uncovered in Xiamen. The scandal centered on smuggling operations run by Lai Changxing, a local entrepreneur who had founded a company called Yuanhua. Some of China's top politicians were implicated in the scandal.
As of the 2010 census, Xiamen had a population of 3.5 million. The Xinhua report said that more than 265,000 trips are made daily on the city's bus system.
There have been other deadly attacks on civilians in Chinese cities in recent years. In May 2011, at least two people were killed and six hurt in explosions at government office buildings in the city of Fuzhou, in Jiangxi Province. State news media reports said the explosions had been caused by a farmer angry at local officials; the farmer's home had apparently been demolished to make room for a highway.
In May 2008, an explosion during the morning rush on a bus in Shanghai killed at least three people and wounded at least 12, according to state news media reports. In July 2008, bombs exploded in two buses in Kunming, the capital of Yunnan Province, killing at least two people. The explosions in both cities, along with violence in the western region of Xinjiang, raised security concerns before the 2008 Beijing Summer Olympic Games.
Five days after the Kunming attack, a group called the Turkestan Islamic Party, which claims to be a jihadist group working for the liberation of Xinjiang, where many ethnic Uighurs are frustrated by the policies of the ruling ethnic Han, put out a video claiming responsibility for the explosions in Kunming and Shanghai.
Chinese officials said their investigations showed that the group was not responsible for the attacks, but it was unclear who had carried them out.
This article originally appeared in The New York Times.