At least 20 people were trapped after an explosion in the canteen of a building housing government offices in the Chinese city of Chongqing in the southwest of the country, state media in China report.
The explosion occurred shortly after noon and is suspected to have been caused by a gas leak.
The explosion caused the building to collapse.
Authorities have sent about 260 rescuers and 50 vehicles to the scene, according to Stat media, according to which the causes of the explosion are now being investigated.
A video posted on the official firefighter profile on the Chinese social network Weibo shows rescuers dressed in orange with helmets actually climbing the debris.
Chinese news agency Xinhua reports that some of the injured have been taken to hospital.