LA officers who caused a giant explosion with fireworks likely made a ‘major miscalculation’

Bomb squad officers who detonated a huge cache of illegal fireworks in Southern California last month, causing a “catastrophic” explosion that injured 17 people – including nine officers and one officer federal – appear to have misjudged the amount of explosive material they detonated, authorities said Monday.

Los Angeles police believed they were detonating about 16 pounds of equipment in the controlled explosion in a neighborhood on June 30, LAPD chief Michel Moore told reporters.

But preliminary results from the Bureau of Alcohol, Tobacco, Firearms and Explosives revealed that they likely detonated more than 42 pounds of explosives, he said.

The device used for the controlled explosion, called a “full containment vessel,” was designed to withstand a maximum capacity of 25 pounds of C4 explosives, Moore said.

“We have some miscalculations that are significant,” Moore said.

In accordance with established practice, officers did not weigh the explosives before detonating them due to their instability, he said. Instead, they estimated the weight and used a remote robot and x-rays to examine the devices.

Among them were 280 M-80s and 44 soda can-sized devices, he said, adding that the officers also appear to have miscalculated the weight of the explosives they used to cause the controlled explosion.

Moore said the explosion that followed was “catastrophic,” causing 17 non-life threatening injuries and damaging or destroying 13 businesses, 22 homes and 37 cars.

“We are committed to identifying how it happened and ensuring that it never happens again,” he said.

Reviews are underway of the bomb squad’s practices, he said, and the officers and supervisor involved have been removed from the field. Moore said the apparent miscalculation was made in “good faith”, although he added that if “mistakes were made I would hold individuals accountable.”

The controlled detonation came after authorities discovered 32,000 pounds of illegal fireworks in the backyard of a house in South Los Angeles. The M-80s and other devices were placed in the containment vessel after investigators determined they were too dangerous to remove.

The suspect accused of purchasing the fireworks in Nevada and storing them at his home was charged earlier this month in federal court with transporting explosives without a license.