A pyrotechnics business in Northern California has confirmed that an unspecified number of its employees were “lost” when a warehouse full of fireworks exploded earlier this week, sparking a wildfire and days-long evacuation for nearby communities.

Seven people are missing after a warehouse holding fireworks caught fire and set off a series of massive explosions in Northern California late Tuesday.

The Yolo County Sheriff’s Office reported Wednesday that the cause of the explosion remains unknown and that it’s still an active evacuation zone around the property. Footage