OAKLEY (CBS SF) — A woman was killed Friday in a residential structure fire in Oakley.

Firefighters with the East Contra Costa Fire Protection District responded Friday at 5:41 p.m. to a structure fire at a residence on Norcross Lane.

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Firefighters arrived at the scene to find thick smoke and heavy fire coming from a duplex, and additional units were called in due to a woman reportedly still being inside the building.

Due to the heavy fire conditions inside the structure, fire units were deployed in a defensive fire attack from the exterior of the building and extinguished the blaze.

Once the fire was extinguished, fire crews conducted a primary search of the unit and found a deceased woman inside.

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Crews conducted a secondary search of the unit and then conducted mop up, salvage and overhaul operations.

There were no reported injuries to firefighters.

The cause of the fire is under investigation.

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