BEIJING — At least 22 people died in a blaze that gutted a two-story workers’ dormitory in eastern China on Sunday, and investigators suspect the fire was the work of an arsonist who used gasoline, according to local news reports.

Police officers arrested a suspect in Yushan Town, Jiangsu Province, Chinese Central Television news reported. But the report gave no motive for the fire, which broke out around 4:30 a.m. in a house serving as a dormitory for 29 or so restaurant workers.

Videos shared on news websites showed residents yelling in panic while firefighters stood outside the building in Jiangsu, and a dense ribbon of smoke rose into the sky. The pictures indicated that the windows were blocked with anti-theft grates, which might have stymied people from jumping to safety. Six people managed to escape, including three who were injured and sent to the hospital. One resident was missing, the reports said.

Safety investigators discovered “traces of burned gasoline at the scene, and the doors had all been locked from the outside,” the State Administration of Work Safety wrote online.