Seven missing after fireworks factory obliterated by massive explosions

Seven people are unaccounted for following a massive explosion at a fireworks warehouse on Tuesday in northern California, officials revealed during a briefing on Wednesday.

The large facility suddenly exploded on Tuesday afternoon, forcing residents in the nearby community of Esparto to flee their homes while fireworks whizzed out of the exploding warehouse.

The blast took place at a pyrotechnics storage facility next to Esparto, sparking several large fires that engulfed nearby buildings, vehicles and vegetation. Due to ongoing safety concerns, drones are being used to survey the area and locate the missing persons, officials stated.

"First responders and investigators are working diligently with the property owner to determine the whereabouts of those individuals," Cal Fire and the Esparto Fire Protection District announced on Wednesday.

The smoke plume from the exploding factory, which continued to emit blasts for several hours, sent a smoke plume up to 15,000ft into the skies over northern California.

Investigators are now probing whether the pyrotechnics facility adhered to the state's stringent regulations and federal explosive storage requirements, as reported by ABC News. The facility is owned by a licensed pyrotechnics operator, according to the fire service

"This type of incident is very rare," officials said in a statement.

Evacuation orders remain in place around the fireworks factory, located in Yolo County, as authorities warn of continued danger near the facility, where explosions continued for several hours after the fire began.

The explosion occurred in the week leading up to the Fourth of July holiday, a period notorious in the US for the highest number of fireworks-related injuries and incidents. Just three days before the event, the warehouse caught fire and exploded, sending fireworks shooting into the air and onto nearby farmland, igniting further fires.

Aerial footage from Tuesday evening revealed at least two buildings and several lorries engulfed in flames, along with numerous smaller fires in the middle of fields, presumably ignited by flying explosive debris.

Ground teams, firefighting aircraft and a helicopter were all diverted to Esparto from the ongoing Brown Fire in Vacaville to the south shortly after 6pm.

A one-mile evacuation zone was set up, although some Esparto residents were permitted to return to their homes.