A warehouse storing fireworks in California caught fire and exploded Tuesday, sending a fireball into the air, launching debris and causing pyrotechnics to detonate above the site, according to officials and video from the scene.

The Yolo County Sheriff’s Office said the warehouse, near the Esparto area northwest of Sacramento, exploded and was actively burning.

It was not immediately clear whether there were injuries.

“We urge everyone to avoid the area so that fire crews and emergency responders can safely do their work,” the sheriff’s office said on social media. “A one mile evacuation area has been placed around the scene.”

Firefighters responded to the area just before 6 p.m., NBC affiliate KCRA of Sacramento reported.

Helicopter video taken by KCRA showed fires at the facility, including at least one building ablaze, and fireworks launching into the air and detonating.

The video shows white smoke rushing from inside the building out through the roof before a large explosion and fireball, with many airbursts from fireworks.

The cause of the fire and explosion was unknown Tuesday night, the sheriff’s office said.

The California Department of Forestry and Fire Protection’s Sonoma-Lake-Napa Unit said it was responding to the commercial and vegetation fire in Yolo County.

Esparto is a community of around 3,000 almost 30 miles northwest of Sacramento.

The explosion happened near the border between Esparto and Madison, which lies to the east, the sheriff’s office said.