Smoke and flames rise at a fireworks warehouse near Esparto, Calif., on Tuesday, July 1, 2025. (KGO via AP)

ESPARTO, Calif. (AP) — An explosion at a fireworks warehouse in northern California caused several fires, sending black smoke into the air and forcing evacuations, authorities said. There were no immediate reports of injuries.

People were urged to avoid the area of Esparto and Madison for several days following the Tuesday night explosion, which set off multiple fireworks and caused a large fire that led to other spot fires and collapsed the building.

“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 Yolo County Sheriff’s Office said in a news release.

The cause of the explosion was under investigation, the office said.

The fire had reached 78 acres (32 hectares) as of Tuesday night, the California Department of Forestry and Fire Protection said.

Esparto is in a rural area about 40 miles (64 kilometers) northwest of Sacramento.

“We do believe this location is owned by an active pyrotechnic license holder,” Deputy State Fire Marshal Kara Garrett told KXTV. She added: “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.”

Gov. Gavin Newsom’s office posted that it was tracking the fire and that state ground and air resources were deployed.

“The State Fire Marshal has sent an arson and bomb investigation team, and stands ready to provide additional support as needed,” the statement said.