LOS ANGELES (CBSLA) — Two more injured firefighters from an explosion in downtown Los Angeles in May have returned to active duty.

A total of 12 firefighters were injured in the fire that broke out in the Toy District on May 16. More than 230 firefighters responded to the scene.

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As firefighters were responding to the blaze inside the building at 327 East Boyd Street, the site of a butane honey oil supplier called Smoke Tokes, there was a “significant explosion,” said LAFD Captain Erik Scott.

A fire in downtown Los Angeles on May 16, 2020, left 12 firefighters injured. The cause is under investigation. (Courtesy: OnScene.TV)

There are now three total firefighters back on the job after the incident. One firefighter remains hospitalized in the burn unit but is expected to return to duty at some point. The remaining firefighters are still recovering at home.

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The official cause is still under investigation but authorities believe the fire and explosion were caused by butane tanks stored inside the business.