Updated

An explosion Saturday at a military-run fireworks factory in northern Vietnam killed at least 19 workers and injured dozens of others, officials and state media said.

Tran Minh Khanh, deputy director of the provincial health department, said the morning explosion injured more than 90 workers, many of them seriously. The bodies of 19 workers were pulled from the wreckage, state media said.

Maj. Gen. Le Quang Dai, the military chief in Phu Tho province, said the search and rescue operation was ongoing to try to find survivors.

Several sections of the multi-building factory were leveled in the explosion, and some nearby homes were also damaged, Dai said.

He said that about 200 workers were present at the time of the blast, but that it was still unclear how many managed to escape. Workers have been working weekends to produce fireworks for the Lunar New Year festival in January, he said.

About 1,000 residents living near the factory were evacuated following the explosion, the online newspaper VnExpress said.

A local police officer told The Associated Press that the explosion could be heard 10 kilometers (6 miles) away, and that it leveled some houses and shattered glass windows in others. He spoke on condition of anonymity because he was not authorized to speak to the media.

The factory is the only facility in Vietnam that produces fireworks to be used for Lunar New Year festivals and other major public events.