By CBS13 Staff

MODESTO (CBS13) — Firefighters who were battling a blaze at a Modesto duplex had to get out quickly before the roof collapsed in on them, authorities say.

The fire happened Wednesday afternoon along the 700 block of Rachelle Drive.

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Modesto Fire says their crews, along with units from Ceres and Stanislaus, responded to the scene and found a single-story duplex quickly being engulfed in flames.

Crews made their way inside and started an aggressive attack and primary search of the garage, bedrooms and common attic.

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However, firefighters say the fire conditions changed rapidly when they were inside. The firefighters evacuated the building – just before the roof failed catastrophically.

The fire was eventually brought under control within 20 minutes

No injuries to either firefighters or any civilians were reported.

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Exactly what started the fire is now under investigation.