Seven people were missing Wednesday following an explosion at a fireworks warehouse in rural Northern California that caused a massive fire that spread to farm fields and forced evacuations in the surrounding community.

Axar.az, citing AP, reports that two people were injured and received medical care, Esparto Fire Chief Curtis Lawrence said at a news conference Wednesday.

Lawrence provided no further information other than to say the two were “OK,” and it wasn’t known if the victims worked at the facility.

Emergency crews and investigators were working with the property’s owner and monitoring the area using drones to find the missing individuals.