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.

SACRAMENTO, Calif. (AP) — Rescue crews were searching on Thursday for seven people still missing days after an explosion at a fireworks warehouse in Northern California shook a tiny farming community and forced the cancellation of nearby July Fourth celebrations.

A number of municipalities across Northern California have put their Fourth of July fireworks shows on hold after the explosion at a fireworks warehouse in Esparto. Cal Fire says seven people are unaccounted for after the massive explosion at Devastating Pyrotechnics on Tuesday.