By CBSLA Staff

SANTA CLARITA (CBSLA) — Four people remained hospitalized Wednesday after receiving critical burns and other injuries sustained in an explosion involving commercial pyrotechnics in Santa Clarita.

Authorities were initially called at about 4:45 p.m. Tuesday to the 25100 block of Rye Canyon Loop for reports of an explosion on a movie set, according to the Los Angeles County Fire Department.

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When fire crews arrived on the scene, they found three patients suffering from critical burn injuries and took them to nearby hospitals. The fourth person took themselves to the hospital.

All four people had “extensive injuries” and were admitted to a trauma center. Two of them were later taken to a burn ward.

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The location of the explosion was later determined to not be a film set, but at a production site where equipment used for the movie industry is stored.

The Los Angeles County Sheriff’s Department said the explosion “was caused by the processing of commercial pyrotechnics, which were owned by a private company.”

Video footage from the area showed large shipping containers, one of which appeared to have significant fire damage.

Fire crews were able to quickly put out a small one-acre brush fire that resulted from the explosion.

Authorities are continuing the investigation into the cause of the explosion.

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(© Copyright 2021 CBS Broadcasting Inc. All Rights Reserved. City News Service contributed to this report.)