A blast in an illegal iron mine in northern China killed at least 24 people and injured five over the weekend, state media reported on Tuesday.
The mine in Wu'an city, Hebei province, was disguised as a boar farm in order to deceive authorities, Xinhua news agency said in its report on Sunday's explosion.
"The owner has violated the law by illegally exploring the state-owned resources. To cover their illegal actions, they have built three walls to cut the farm out from the outside," Xinhua quoted Wang Haibo, an official with the Wu'an city government, as saying.
China is home to the world's deadliest coal mining industry and despite government safety drives has a grim record of industrial accidents, in part because high prices for resources are tempting owners to produce illegally or beyond safe limits.
The owner of the Wu'an farm, which was privately held, fled the scene and was still at large.
The explosion happened in a tunnel whose entrance was located in one of the pigpens, the report said, but the cause of the blast was still unknown and the local government was investigating.