PETALUMA (KRON) -- Building officials say it appears a bulld-up of standing water in overnight storms is responsible for the roof collapse at the Petaluma Goodwill warehouse.

Witnesses say the collapse happened at about 10:45 a.m. Thursday at the Goodwill Industries facility on Lakeville Street in Petaluma.

There are no confirmed reports of injuries from the collapse.  Video from the scene shows a large section of the roof buckled in.  Petaluma firefighters are monitoring the scene while engineers try to determine the structural integrity of the building.

Stay tuned to KRON 4 and KRON4.com as storms continue to move through the Bay Area over the next couple of days.

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