The man, whom police identified as Ji Zhongxing, born in 1979 and from the city of Heze in Shandong province, was then taken to a hospital, according to CCTV.
Apparent witnesses posting pictures of the incident online said the man in the wheelchair had warned them to stand back before the explosion.
“It was pretty powerful. You could feel it in your chest,” said Stephanie Kleine-Ahlbrandt of the International Crisis Group think tank, who was in the terminal during the blast. “There was dust, smoke, people running away, police, people running in to take pictures.”
Reached by phone, Beijing police said they had no information about the incident.
In a 2006 blog entry on a popular Chinese forum, a man named Ji Zhongxing described being severely beaten in 2005 by local authorities while he was earning money by giving rides on his scooter. Wielding steel batons, officers broke his back, paralyzing him from the waist down, he wrote.
The blog was taken down Saturday night, but it was unclear whether it was removed by government censors, a common reaction in China to online content considered sensitive or threatening to government authority.
The blog entry described the beating in detail and listed witnesses’ names as well as contacts for the man’s relatives and lawyer, but no one answered at those numbers Saturday night.
Pictures and descriptions of a man in a wheelchair shouting before the explosion were posted on the Chinese equivalents of Twitter, called weibo. Online photos showed police and medics crowded around an overturned wheelchair in the aftermath.
“You could see something that looked like a machine on the ground at what seemed like the epicenter of the blast,” said Kleine-Ahlbrandt, who had arrived at the airport on a domestic flight. The blast, she said, appeared to have occurred near the baggage claim, in the area where relatives wait to greet arriving passengers.
Bombings and other violent acts are not unheard of in China, especially in rural areas with ethnic unrest, but they are rare in Beijing, which is heavily controlled and surveilled by Chinese authorities.
Public anger at police and security officials, however, is common in China, especially among the country’s many migrant workers, who are often beaten and harassed for working street jobs without licenses.
The blog posting said that on June 28, 2005, Ji had passed the city of Dongguan’s public security office while ferrying a passenger. At least seven security officers emerged and began beating him and his passenger, breaking Ji’s back, according to the blog.
His family reported the incident, but local authorities denied beating Ji and said they emerged from the building to rescue him from hooligans who were beating him, according to the deleted blog. Ji and his family were saddled with medical fees, it said.
A note at the bottom of the blog posting from 2006 explains that it was compiled on Ji’s behalf by Wu Xiande, a blogger who others in the activist community said has often helped government petitioners write and post their experiences and complaints.
The blog quotes someone identified as Ji Zhongxing’s brother saying, “Because we are farmers living in poverty, no matter who we turned to, no one of them took up our case.
“We cried to the sky, the sky didn’t listen. We cried to the earth, the earth kept silent. We cannot find justice.”
Zhang Jie in Beijing contributed to this report.