STEFANIE DAZIO, Associated Press
Los Angeles bomb technicians grossly miscalculated the weight of homemade fireworks last month when they detonated them in a containment chamber, causing a catastrophic explosion that injured 17 people and rocked a neighborhood, the police chief said Monday.
Chief Michel Moore said five members of the department’s bomb squad have been removed from field duties as the investigation continues. They could face discipline.
The explosion was highly unusual, officials say, and has prompted the Los Angeles Police Department and FBI to review police protocols regarding the detonation of explosives. The Police Department is now requiring a captain to sign off on detonations, in addition to the two bomb technicians and a supervisor who are already required.
Residents in the neighborhood have called for accountability and asked why some people were still in their homes, despite a door-to-door evacuation order. Fireworks are illegal to sell or possess in Los Angeles and in unincorporated areas of the county.
The explosion came after police had spent the day disposing of thousands of pounds (kilograms) of commercial-grade fireworks that were found in a South Los Angeles home following an early-morning tip. Those fireworks were detonated at an off-site location.
However, officers also found homemade fireworks that were leaking and the bomb squad decided to detonate them in the neighborhood — believing they were too unstable to transport elsewhere. They examined them by X-ray and robotics and loaded them into the detonation chamber, officially called a total containment vessel.
The bomb technicians — without using a scale, as is allowed by Los Angeles police procedures to avoid additional handling of the unstable devices — estimated the weight of the homemade explosives and a counter-charge to be about 16.5 pounds.
They arrived at 16.5 pounds by estimating that the smaller explosives — there were 280 of them — each weighed about a half an ounce in a standard flash powder measurement. The bomb technicians estimated that the 44 larger explosives — which were about the size of a soda can with a fuse — had about 1.5 ounces worth of flash powder.
Federal authorities who weighed the remains after the blast calculated that the weight was actually more than 42 pounds (19 kilograms). The smaller explosives were actually 1.37 ounces and the larger ones were about 5 ounces.
The detonation chamber’s maximum capacity is 15 pounds for multiple uses or 25 pounds for a single use, Moore said. The LAPD has not publicly identified the manufacturer of the detonation chamber, despite repeated requests.
The truck-mounted chamber used during the June 30 explosion had been in service for a decade and this was its 42nd time in use.
Nine police officers and a federal agent were among the injured. One officer was taken to the hospital and is now recovering at home.
Authorities say they are also investigating whether the detonation device had a defect.
The department is also looking at the practices of bomb squads nationwide to see if its standards are up-to-date. If the Los Angeles bomb squad is found to have been following the police department’s protocol but, in fact, the department’s procedures turn out to be inaccurate, Moore said the technicians will not be disciplined.