WATCH LIVE: Ontario fireworks explosion, structural fires immediate response from firefighters in residential neighborhood

ONTARIO, Calif. (KABC) – A major explosion sparked several fires in a structure in an Ontario neighborhood on Tuesday afternoon, prompting a response from emergency personnel.

The incident occurred shortly after 12:30 pm in the South San Antonio Avenue and West Maple Street area, breaking nearby windows and sending a large cloud of smoke into the air.

“We are aware of the strong explosion that was heard recently,” said a brief statement from the city’s official Twitter account. “The Ontario Police Department and the Ontario Fire Department are investigating. Please stay away from the area.”

Whether anyone was seriously injured is not immediately known.

A later tweet from the city said the fire broke out after “a large number of fireworks in a house were lit.” At least one other house was also on fire, along with several external structures on a ranch-like property.

The AIR7 HD news video showed firefighters rescuing a horse that was trapped in an enclosure, with fires burning dangerously close.

Residents as far away as Anaheim and Huntington Beach reported having felt reverberations since the initial explosion.

DEVELOPMENT: More details will be added to this report as they become available.