ALAMEDA -- A smoke detector alerted a man and woman of a fire in their front room Tuesday morning that caused about $180,000 in damage, firefighters said.

The man and woman, who firefighters described as related but not married, were outside when crews arrived about 6:40 a.m. and began extinguishing the blaze at the College Avenue residence.

The fire was knocked down within 10 minutes and declared under control just after 7 a.m.

The woman suffered a non-life threatening injury during the incident and was treated at Alameda Hospital, fire Capt. Jim Colburn said. A firefighter was also slightly hurt.

The fire is believed to have started accidentally in the front room of the single-story home, which is in the 1000 block of College Avenue.

Damage was estimated at $150,000 to the structure and $30,000 to the contents, Colburn said.

Twenty firefighters responded after the fire was reported at 6:37 a.m. The Red Cross also responded to assist the residents.

Reach Peter Hegarty at 510-748-1654 or follow him on Twitter.com/Peter_Hegarty.