A fire in a clothing factory in Bangladesh's capital late Wednesday killed at least eight people including a police officer and the factory owner, police and the factory's general manager said on Thursday.

Zabidur Rahman, the general manager of the factory, said the fire broke out on the third floor of the 11-story sweater factory in Dhaka's Mirpur district. Mohammad Mahbub of the Bangladesh Fire Service said the factory was closed and there were no workers inside when the fire broke out at 11 p.m. local time. The factory belonged to Tung Hai Group, a large garment exporter.

"It is not clear to us how the accident happened, but we are trying to find out the cause," Mohammad Atiqul Islam, president of the Bangladesh Garment Manufacturers and Exporters Association (BGMEA), told Reuters.

The Bangladesh government on Wednesday said it shut down 18 garment factories for safety reasons following the April 24 collapse of another factory, Rana Plaza, on the outskirts of the city. Six were cleared to re-open on Thursday after inspectors deemed the factories safe and issued safety certificates.

The number of people confirmed to have been killed from the Rana Plaza complex collapse reached 912 this week, it was announced Thursday by a spokesperson at the army control room coordinating the operation to pull bodies from the rubble. Roughly 2,500 people were rescued from the building.