One man died in a fire at a mobile home in San Marcos on Tuesday, officials said.

The fire broke out around 11:45 a.m. Tuesday in a single-story, double-wide mobile home at 1219 E. Barham Drive, east of La Moree Road and south of Highway 78, according to the San Marcos Fire Department.

A man in his 50s, who was the sole occupant of the residence, was killed, Battalion Chief David Pender said. The victim was not identified pending notification of next of kin.

Pender said the San Diego County Sheriff's Department's Bomb/Arson Unit is investigating the cause of the fire.

Damage estimates were not immediately available.

The Escondido Fire Department assisted with the firefighting effort.