Authorities in northeast China's Heilongjiang Province have ordered all nine fireworks factories in the province to shut down after a blast at one of the plants on Monday killed 20 people.

"We have ordered all nine fireworks factories in the province to stop production immediately. We have rescinded their permits for production," a Heilongjiang Provincial Work Safety Administration spokesman said Thursday.

The nine factories have been ordered to dismantle their production facilities by the end of the month and to dispose of their fireworks-manufacturing materials by Sept. 15.

In addition to causing the 20 deaths, the explosion at the fireworks factory in the Wumahe District of Yichun City Monday injured 153, while four others are still unaccounted for.

Three government officials and two factory executives have been sacked or detained over the deadly explosion, according to a Wednesday statement from the Yichun City Committee of the Communist Party of China.

Zhao Weiqiang, deputy head of Wumahe District and in charge of work safety, has been removed from his post.

Cheng Chuanxin, head of the Wumahe District Work Safety Bureau, has also been removed from his post.

Police have detained Liu Chunya, a safety inspector at the bureau, for dereliction of duty.

Jin Chaoxiang, head of the fireworks factory, and Zhou Shiji, deputy head of the factory, have also been detained.

A preliminary investigation showed the plant was illegally producing fireworks, as the local work safety department canceled its production permit in June, a statement issued Tuesday by the State Administration of Work Safety said.

The plant was requested in June to suspend production and improve factory safety, according to the statement.