Los Angeles police attempting to safely detonate a stash of illegal fireworks last month significantly underestimated the weight of the devices before they exploded, injuring 17 people in a South L.A. neighborhood.
The miscalculation, disclosed at a news conference on Monday, is the first major revelation from a massive investigation into the cause of the blast that devastated an entire block after police discovered more than 32,000 pounds of illegal fireworks at a home on 27th Street.
Some of the explosives, including 280 M-80s and 40 soda can-sized devices, were deemed too dangerous to transport and were placed in an armored truck for a controlled detonation. Police estimated the weight at 16.5 pounds, but federal investigators later determined that the weight was closer to 42 pounds, said LAPD Chief Michel Moore.
The miscalculation, Moore said, could have resulted because bomb squad officers, following safety protocols to limit the handling of explosive devices, were unable to use a scale to weigh them. The estimates, he said, were made by a physical inspection.
"For unknown and improvised explosive devices - including this type of firework - it's recommended to minimize the handling of these items as much as possible," Moore said.
"If mistakes were made in regards to established protocols, I'll hold the appropriate individuals accountable," he said. "This department will learn from others."
The revelation could increase scrutiny of how the LAPD handled the incident and whether it could have done more to protect residents and get the explosives out of the densely populated area before they were detonated. Moore said the supervisor and bomb technicians involved in the incident have been removed from the field and that the investigation, which includes the federal Bureau of Alcohol, Tobacco and Firearms, is ongoing. The FBI has also agreed to conduct its own review into LAPD's systems and protocols to ensure the department is in compliance.
L.A. City Councilman Curren Price Jr., responding to the findings, called the incident "by far one of the LAPD's largest blunders in recent history."
"The actions taken by LAPD on June 30 fell short of law enforcement's duty to protect and serve, and this act of negligence bears serious consequences not only for the victims, but for our community and the city as a whole," Price said.
Price added: "As we wait for the final report to be released, I hope LAPD is taking the actions now to address their shortcomings and are making plans to step up and support the victims of the devastation who have been traumatized and will be suffering from the effects for years to come."
The explosion sent 10 LAPD officers, one ATF officer and six civilians to the hospital, Moore said. Thirteen businesses, 22 residential properties and 37 vehicles were destroyed, he said.
"I want to personally express my apologies to every resident, business operator and customer that was traumatically impacted by this incident," Moore said at the news conference. "I'm so sorry that this occurred."
Federal officials discovered the fireworks underneath a brown tarp in the backyard of the house. More than 140 homemade "M-devices" were also uncovered, along with hobby fuses and other explosives-making materials.
The homeowner, Arturo Ceja III, 27, was arrested July 3 and charged with illegally transporting tons of explosives. Prosecutors allege that the devices were purchased from a dealer in Pahrump, Nevada.
