Los Angeles Police Department bomb squad officers apparently made a “significant” miscalculation that caused a “catastrophic” blast that injured 17 people–including nine LAPD officers and a federal agent–when they tried to set off a contained detonation of fireworks last June, NBC News reports.
Using video from a robotic camera, technicians calculated that they had found 16 pounds of fireworks in a house and attempted to minimize damage from a controlled explosion using a “total containment vessel,” basically an armored truck designed to sustain a blast of 25 pounds of C4 compound. Instead, they detonated an estimated 42 pounds of explosives, causing a massive blast that rocked a South LA neighborhood.
“We have miscalculations that are significant,” LAPD Chief Michel Moore said, summing up the finding of the investigation. Five members of the bomb squad have been removed from duty, Moore said.
According to the report, 13 businesses, 22 residential properties and 37 vehicles were damaged or destroyed by the explosion that sent a mushroom cloud more than 100 feet into the air.
The technicians did not weigh the material because they thought the explosives were unstable. They miscalculated the weight, which led to the massive explosion.