ONTARIO, Calif. (KTLA) – Two people died in a fire sparked by commercial-grade fireworks at a home in Southern California Tuesday afternoon, officials said.

Towering billows of smoke were still rising from the house in Ontario, east of Los Angeles, more than an hour after authorities first responded. A news helicopter with Nexstar station KTLA was flying overhead as firefighters tried putting out the blaze just after 1 p.m., when bright red flames were still visible through the home’s windows.

Officials later confirmed two fatalities and the wounding of a horse and dog. The blaze also led to an evacuation of homes in the surrounding area, authorities said.

Firefighters received a call about an explosion at 12:28 p.m., Ontario Chief Ray Gayk said during a news conference later in the afternoon. He said the first responders saw flames upon arriving to the home located along West Francis Street.

“That’s when we noticed the fire had started,” Gayk said. “It appeared to be commercial-grade fireworks.”

He said investigators with the department’s bomb squad, FBI and ATF were still going through the area to make sure no explosives were left about three hours after firefighters responded.

Ontario Police Lt. Russell said police had also received reports of a loud explosion. City officials later said those were the sounds of fireworks going off.

More than an hour after authorities arrived, around 1:45 p.m., firefighters could still be seen hosing down the house and mopping up the surrounding area.

The fire department issued an evacuation order for the immediate area and set up a temporary reception facility at a nearby community center.

Check back for updates to this developing story.