BERKELEY -- A smoke alarm likely saved a woman when a fast-moving fire tore through her Berkeley cottage Monday evening, fire officials said.

Fire crews responded about 6 p.m. to calls of a woman screaming and a building on fire at 1708 Martin Luther King Jr. Way, said Gil Dong, interim Berkeley fire chief.

"When you get calls like that we're thinking rescue," Dong said. "The first arriving engine found a cottage behind an apartment building engulfed in flames. We were able to knock down the fire and prevent it from spreading to the adjacent buildings."

The woman was alerted to the fire by her smoke alarm, Dong said, because she was not in the same room where the fire started. The department is investigating the cause.

Dong said because the fire looked like it might spread to the adjacent buildings, firefighters called in reinforcements.

No injuries were reported and Dong said the fire caused about $50,000 in damage to the 700-square-foot cottage. The woman who lives there lost about $20,000 worth of property, Dong said.

Monday evening was busy with multiple medical calls, so Dong said the Alameda County and Albany fire departments were on standby to help with other incidents in Berkeley.

Doug Oakley covers Berkeley. Contact him at 510-843-1408. Follow him at Twitter.com/douglasoakley.