Large explosions believed to be caused by commercial-grade fireworks left two dead and at least three injured in the city of Ontario, Tuesday.

Ontario Fire Chief Ray Gayk said a series of explosions went off in a neighborhood within West Maple Ave., West Francis St., South Fern St. and South San Antonio Ave., setting fires to multiple houses in the area and forcing residents to evacuate.

Investigators did not yet determine exactly what type of explosives went off, but they strongly believe commercial-grade fireworks were the cause, according to Fire Cheif Gayk.

“They’re commercial grade, the type of explosives we believe that you would normally see at a firework show,” Gayk said. “That’s just totally speculation at this point, based upon what we were seeing.”

Caught on video from a distance and posted to social media, a billowing cloud of smoke filled the sky and the fireworks could be heard going off for several seconds.

Nearby residents said the explosions shook the neighborhood, shattering windows setting off car alarms and creating a smoke cloud that could be seen from surrounding freeways.

The incident required 50 Ontario Fire personnel, including the Ontario Fire bomb squad to clear the area of any further possible explosives.

The investigation is being led by Ontario Fire, its arson unit, Ontario Police Dept., the FBI, the Bureau of Alcohol, Tobacco, Firearms and Explosives and the Calif. State Fire Marshal, as they work to determine exactly what type of explosives went off and where.

Gayk said they expect to be clearing debris for several days and evacuated residents could stay at a temporary Care and Reception Center is being established at the De Anza Community Center.

This post will be updated when additional information becomes available.

LA Weekly