LOS ANGELES — Seventeen people, including police, were hurt when a large explosion rocked a Los Angeles neighborhood Wednesday evening as thousands of pounds of illegal fireworks were being seized, officials said.
None of the injuries were life-threatening, police said.
The blast happened about 7:30 p.m. local time (10:30 p.m. E.T.) as the bomb squad was detonating some of the explosives in a vehicle with a containment vessel designed to withstand blasts.
"This vessel should have been able to safely dispose of that material," LAPD Chief Michel Moore said Wednesday night.
"And you saw the resulting damage, and the total catastrophic failure of that containment vehicle," Moore said.
The blast destroyed the vehicle, overturned a nearby car and shattered windows in homes and businesses.
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Three people in the area suffered moderate injuries, and three others suffered minor injuries, officials said. One additional person was treated at the scene, but was not taken to a hospital. Nine LAPD officers and a federal Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) agent also suffered minor injuries.
Approximately 5,000 pounds of fireworks and explosives were found at a home in the Historic South-Central neighborhood Wednesday morning, police said.
A 27-year-old man who has been arrested is accused of bringing the explosives in from out of state to resell for the July 4th weekend. He faces a charge of possession of a destructive device. He may face additional charges for child endangerment because his 10-year-old brother lives at the home, Moore said.
The pyrotechnics were commercial-grade, but some were described as improvised explosive devices with simple fuses that were considered more unstable, Moore said.
They were X-rayed and cut open by robots to assess, he said, and less than 10 pounds were detonated inside the bomb squad containment vessel, which is rated to withstand more material than that.
"Something happened in that containment vehicle that should not have happened, and we don't know why," Moore said. "But we intend to find out why."
Los Angeles Mayor Eric Garcetti said in a tweet that he had directed the LAPD to conduct a full investigation, "so we can better understand why this happened."
Officials said it was fortunate no one was killed, and used the incident to highlight the danger of illegal fireworks, especially when people intent on selling them store the explosives in residential neighborhoods. The ATF will also investigate how the fireworks and explosives were acquired and transported to Los Angeles as well as the circumstances of the explosion, the police chief said.
In March, a massive fireworks explosion at a house in Ontario, a city about 40 miles east of Los Angeles, killed two people. Officials said at the time that the blast caused at least $3.2 million in damage.
Wednesday's explosion in Los Angeles comes days before the July 4th weekend.
This year, officials have vowed to crack down on illegal fireworks. Los Angeles, like most of California, is under an extreme drought, according to drought monitors.
Last week, Los Angeles City Attorney Mike Feuer said his office sent cease and desist letters to Facebook Marketplace, Craigslist and others over online sales.
Police in South Gate, a city in the Los Angeles region, said last week that it arrested a man with 800 pounds of illegal fireworks and found 1,200 more in a rental truck.