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 still "unaccounted for" in Yolo County's town of Esparto after several explosions at a fireworks warehouse resulted in a fire, officials said.

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