A man in a wheelchair with an apparent grievance has detonated a small device at Beijing International Airport.
The man, named by state media as Ji Zhongxing, 34, from central Shandong province, was injured and taken to hospital.
No-one else was hurt in the blast, which filled part of the Terminal 3 arrivals hall with smoke.
An online microblog attributed to the man says the explosion was to protest at his ill-treatment by Chinese police.
The blog suggests his lower body was paralyzed after he was alleged to have been heavily beaten by security agents in southern China in 2005.
Mr Ji, who is alleged to have been operating an unlicensed motorbike taxi service, was also apparently dissatisfied with the way his complaints against the authorities had been dealt with.
State news agency said he detonated the device – a package of gunpowder taken from fireworks – after being prevented from distributing leaflets.