LOS ANGELES, Calif. — (AP) — Investigators are combing the wreckage of a fire and explosion at a downtown Los Angeles vape and marijuana accessories wholesaler as six burned firefighters remained in the hospital.

The Bureau of Alcohol, Tobacco, Firearms and Explosives on Monday sent special agents to help reconstruct the scene, identify where the fire started and determine a cause.

Firefighters were at the commercial building Saturday when there was an explosion that sent them scrambling through searing flames to get out of the building. Twelve were injured. All are expected to survive.

City officials do not have any records of a license or a commercial cannabis application for the supplier.