2 brothers killed after accidentally triggering explosion in Bell Gardens

The Los Angeles County Sheriff's Department described Tuesday's deadly explosion at a Bell Gardens apartment complex as a "tragic accident" caused by homemade explosives, possibly fireworks. 

Investigators believe one of the half-brothers — Carlos Hernandez, 13 and Christopher Benitez, 23 — mixed energetic powders and may have pressurized the mixture, sparking the blast.  Lt. Michael Modica said an example of energetic powders is gunpowder.

"We believe they were responsible for the explosion," Modica said. "At this point, we believe it was a tragic accident."

Detectives found pieces of plastic pipes at the scene along with energetic powders, which have been sent to their lab for testing. 

"I keep saying that people just don't understand how dangerous this stuff can be," Bell Gardens Police Chief Paul Camacho said. "I think as a result of what we see behind us that is the consequence of not following the laws and not doing what you're supposed to do."

The explosion also hospitalized a young boy, who was in stable condition on Tuesday, according to the LA County Fire Department. The family said the boy was a relative of the half-brothers.

It caused significant damage to the apartment complex, destroying part of the second floor and the roof. 

Camacho said about four to five families were displaced after inspectors red-tagged the building and marked it for demolition. 

"I just don't really know what's going to happen to us," neighbor Wendy Gutierrez said. "Where are we going to end up?"

The family said Hernandez was an altar server at his local church. Benitez served in the National Guard.