Police say an illegal THC extraction lab inside the garage of a Tarzana home caused a devastating fire and explosion.

The investigation began with a 911 call about a fire on Redwing Street, just south of Ventura Boulevard, before 11 p.m. Thursday. Firefighters determined the blaze caused an explosion inside the attached garage, although the flames were extinguished in about 20 minutes.

But as investigators examined the scene, they quickly discovered signs of illegal activity and shared the information with the LAPD.

Authorities said Monday that an explosion that rocked a Valley Glen residence and sent two people to hospitals was likely caused by equipment used in a marijuana grow operation on the property.

“We met with firefighters and they informed us that they had found what they believed to be a possible clandestine THC lab located in the garage,” LAPD Detective Cecil Mangrum said.

A 26-year-old woman and a 52-year-old man were hospitalized in critical condition after the blast, which witnesses described as “terrifying”.

“I was sitting in a restaurant and I heard a loud explosion,” recalls Justin Yacobi. “I saw fire, flames and debris, and I’m quite shocked by what happened.”

Another witness said the blast sounded like a “big nuclear explosion”.

“It’s unlike anything I’ve ever seen before,” the man said. “It was terrifying. Honestly, it looked like a war was brewing.”

Detective Mangrum confirmed the explosion was “big”, blasting the entire rear of the garage.

Those who cannot return home are accommodated in a hotel. And although they have received help from the city, many do not consider it fair.

“The people who operate these clandestine labs have minimal training and don’t understand the dangers of the chemicals they use, flammability,” Mangrum said.

“Fans trying to make a quick buck lead to things like this: property damage and sometimes even death.”

Police also say the amount of cannabis products discovered at the scene appear to be for sale and not for personal use.

This story first appeared on Telemundo 52’s sister station NBCLA. Click on here to read this story in English.

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