Multiple police and fire departments responded to the scene – about 35 miles east of downtown Los Angeles – at around 12:30 p.m. PST. A house was on fire, the department said.
Dramatic cell phone video shows fireworks and a plume of smoke rising above the scene.
“An explosion of that magnitude, I imagine there is some damage to the houses right next door,” said city spokesman Dan Bell.
Reina Jimenez, who lives close to the blast area, told CNN there were at least three explosions.
“The first explosion was like an earthquake or as if something fell outside of us,” Jimenez said. The second explosion was bigger and louder. It shook the whole house … My husband started filming when the third explosion went off. It was also very big and loud and shook the house again. We were worried that the explosion would hit the house so we started getting the kids ready to leave. ”
The deaths were “in the area” of the explosion, and the two individuals have not been publicly identified, Bell said. There were people in the house who, according to a spokesperson for the fire service, could escape safely.
One more minor injury was reported, the fire officer said. The explosion is under investigation.
Evacuations were ordered for at least three nearby streets, and firefighters warned residents to stay away.
Multiple structures were damaged and covered in debris, the firefighter said. At least one horse was released by firefighters from the immediate area.
Fireworks are banned in the city and cannot be sold, bought, stored, used or transported in the city, officials told CNN.
Jimenez told CNN that her family has heard loud fireworks going off in the area for the past five years.
“About once a week, one or more goes in the summer or by July 4th, and we’re just getting used to it,” she said.
However, people have previously complained on the Ring neighborhood app about the problem, she said.
CNN’s Alexandra Meeks and Jessica Myers reported from Los Angeles and Amir Vera wrote and reported from Atlanta. CNN’s Janine Mack contributed to this report.