Beijing’s international airport was hit by an explosion Saturday after a man in a wheelchair detonated an improvised bomb in protest over ill-treatment by Chinese police.

The man, identified as Ji Zhongxing, from Shandong province, hurt himself after igniting the home-made explosive in the airport’s Terminal 3.

Several witnesses said the man was shouting and waving a white package in the air but no one paid attention to him in the busy airport until the explosion.

The blast caused panic and confusion as white dust and smoke spread through the arrivals hall. No one else was injured and flights were not affected, Xinhua news agency reports.

Police said Ji set the explosive off after being prevented from distributing leaflets. There was no immediate details on the content of the leaflets.

A blog claimed Ji had an apparent grievance against police, after he was allegedly beaten by police in 2005, causing his lower body to be paralyzed.

Ji has drawn support from Chinese citizens who empathize with his “frustration” over the country’s petitioning system, reports AFP.

They also cited Ji’s small act to warn others before he triggered the explosive.

“It’s a big step forward… because Ji chose to inflict the smallest amount of injury,” one Sina Weibo user said.