A 44-year-old woman was killed yesterday morning after a fire broke out in the bedroom of her Silver Spring home.

Montgomery County fire officials said Betty Merrill of 9313 Caroline Ave. died of smoke inhalation after the mattress in her bedroom caught fire shortly before 7:30 a.m.

Neighbors said the victim lived alone in the small bungalow without electricity or a telephone. She also owned a small cottage next door, where her 18-year-old son Michael was sleeping. According to neighbors, Merrill's son discovered the fire and ran to nearby Montgomery Blair High School to report the blaze.

Firefighters arrived on the scene at 7:43 a.m., but the flames in the bedroom were nearly out. Fire officials said yesterday a smoke detector alarm was found in the house, although there were no batteries in it.

Neighbors said Merrill had four other children in addition to Michael, but none was home at the time of the fire.

More than 30 cats and two dogs shared the brown bungalow with Merrill, neighbors said yesterday. They also recalled yesterday that candles could often be seen flickering in the house windows.

Fire officials said the cause of the blaze is under investigation.