LOS ANGELES, Calif. (KTLA) — An “apparent miscalculation” is suspected in the fireworks explosion that shook a South Los Angeles neighborhood late last month, according to a preliminary findings released Monday.
What was meant to be a safe detonation of homemade fireworks ended in an explosion that injured 17 people on June 30 in the 700 block of East 27th Street, where police had spent the day seizing a large cache of fireworks from a home.
Officials said a Los Angeles Police Department squad opted to detonate some of fireworks that were “leaking” and they deemed to be too unstable to move. They loaded the explosive material into a total containment vessel, which is designed to entirely contain the explosion to make sure there’s no risk to people nearby, according to LAPD.
The officers estimated they were putting in 16.5 pounds of explosives into the vessel, which is designed to take a maximum capacity for a one-time detonation of 25 pounds, LAPD Chief Michel Moore said in a news conference Monday.
But investigators later calculated that just over 42 pounds of net explosive weight was in the vessel, Moore said.
“Based on information gathered at this point, it is believed that the net explosive weight placed into the [vessel] exceeded its rated capacity,” Moore said.
Moore said the department believes “human error” led to the miscalculation of the amount of material going into the vessel, explaining that the LAPD team calculated the weight of the explosives by slicing into two firework samples, extracting material from inside, and estimating the weight — not by using a physical weight measure.
Another theory is that the vessel or some of its components failed, according to Michael Hoffman, assistant special agent with the Bureau of Alcohol, Tobacco, Firearms and Explosives in Los Angeles.
The investigation is still ongoing. A specialist is looking for any anomalies or deficiencies in the containment vessel and its components, according to Hoffman.
The LAPD supervisor and bomb technicians involved in the detonation have been removed from the field, Moore said.
“If mistakes are made in regards to established protocols, I’ll hold the appropriate individuals accountable,” the chief said.
Moore apologized to residents affected by the blast, which injured residents and damaged nearby homes and vehicles.
“I want to personally express my apologies to every resident, business operator and customer that was dramatically impacted by this incident … I acknowledge that there are many more individuals who were traumatized by the explosion itself,” the chief said.
The LAPD is now its protocols regarding the detonation of explosives.
“We have taken significant steps to strengthen operating protocols, documentation, oversight of any destruction of fireworks and other explosive materials in the city, and more work remains in this aspect of this investigation,” he said.