YOLO COUNTY — Seven people were missing Wednesday afternoon, a day after a warehouse storing fireworks exploded in Yolo County, authorities said.

The explosion also sparked a vegetation fire and triggered evacuations.

Fire and emergency crews remained at the Oakdale Fire into Wednesday afternoon. According to Cal Fire, it had burned 78 acres and was 0% contained at 1:30 p.m. Cal Fire said crews were in communications with the property’s owner and were using that information and drones in their attempt to find the missing people.

People first reported the fire just after 6 p.m. Tuesday near County Road 23 and County Road 86A in Esparto, a small rural town roughly 37 miles west of Sacramento, according to Cal Fire.

The Yolo County Sheriff’s Office described the explosion as “significant.” Video footage from the scene captured fireworks whizzing through the air and exploding, smoke pouring from the building and eventually the massive explosion of the structure itself.

An evacuation zone remained in place around the property Wednesday afternoon, but residents of neighboring Madison and the Madison Migrant Center were allowed to return home starting Tuesday night, according to the Sheriff’s Office.

“The fire will take time to cool, and once it does, explosive experts must safely enter the site to assess and secure the area,” the sheriff’s office said in an incident update.

The Sheriff’s Office also urged the public to continue avoiding the area for the next several days “so that fire crews, law enforcement, and emergency personnel can do their jobs safely and effectively.”

Authorities told a Sacramento TV station that fireworks were at the location.

“We do believe this location is owned by an active pyrotechnic license holder,” Deputy State Fire Marshal Kara Garrett told KXTV. “This type of incident is very rare, as facilities like this are required to not only follow our stringent California pyrotechnic requirements, but also federal explosive storage requirements.”

The cause of the explosion is under investigation.