(AP) RAYNHAM, Mass.

An 83-year-old woman and her disabled son have died in a three-alarm fire at their Raynham mobile home that appears to be accidental.

The fire was reported about 2:20 a.m. Monday, and the home was fully engulfed when firefighters arrived. It took nearly 40 minutes to knock down the blaze.

The victims and a dog's body were found near the master bedroom. Fire Chief James Januse (juh-NOOSE') believes the 61-year-old man may have been trying to save his mother.

Officials did not immediately release the names of those killed.

State Fire Marshal Stephen Coan said it was likely that improper disposal of smoking materials caused the fire, which began in a deck area behind the home.

Coan said there were no signs of smoke alarms in the home.

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