Federal ATF agents recovered a 500-pound lid from a backyard blocks away from where it blew off during a police bomb squad disposal of illegal fireworks in a South LA neighborhood on Wednesday.
Some 45 agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives' National Response Team fanned out Friday into the neighborhood to try and determine why the blast happened.
They mapped the area of the explosion using helicopters and cameras and collected evidence in the hope of solving why the vessel exploded, said Michael S. Hoffman, the assistant special agent in charge at ATF in Los Angeles, during an afternoon news conference.
He gave no further details about the cause of the blast.
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Work continued, meanwhile, to get the community back to normal. Authorities began escorting residents back into their homes to retrieve belongings such as cars, clothes and medication.
But the area remained shut down with no timeline to reopen. Hoffman said agents will work through the holiday weekend and into early next week.
Community members can go to 27th and San Pedro where officers can help. Also residents can go to Fred Rogers Rec Park where the Red Cross is set up. A shelter is also open to help people who live in the neighborhood. For more information click here.
The explosion happened around 6:40 p.m. Wednesday in the 700 block of East 27th Street, near San Pedro Street, police said.
Among the injured were 10 law-enforcement officers. Those injured in the blast ranged in age from 42 to 85 years old. One declined transport to a hospital. An 85-year-old woman, 60-year-old man and 51-year-old woman suffered moderate injuries, according to the Los Angeles Fire Department's Margaret Stewart. The remaining patients, including the 10 law enforcement officers, suffered minor injuries.
Arturo Cejas III, 27, was arrested in connection with the illegal fireworks.
The force of the blast destroyed the container -- and damaged nearby homes, shattered glass in the neighborhood and caused damage to several cars parked on the street.
At least a dozen homes were damaged, and the damage extended at least half a block from the blast.
The fireworks were brought from out of state for resale to members of the community, officials said.
Police also found 40 "Coke-can sized" devices with fuses attached and 200 smaller devices.
City News Service contributed to this report.