LOS ANGELES (CBSLA.com) — Crews put out a stubborn structure fire Tuesday morning in a one-story commercial building in South Los Angeles.

The blaze was seen burning at 11620 South Main Street near Imperial Highway and Main Street around 7:45 a.m., according to LAFD spokesman Brian Humphrey.

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More than 100 firefighters extinguished the flames in about an hour and 20 minutes, Humphrey said.

The metal clad structure appeared to be a mattress recycling location and/or a body shop business, according to reports.

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No injuries were reported.

Investigators were seeking the cause of the fire, which apparently began outside the single-story building and spread to the structure, Humphrey said.

A damage estimate was not immediately available.

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