A three-alarm fire destroyed a multifamily house in Lynn on Tuesday, fire officials said.

“The battle is lost. At this point they’re just trying to protect anything else that isn’t on fire,” said district fire Chief ­Arthur Richard.

No injuries to the occupants were reported, except for a dog that died, Richard said.

The fire, which struck the two-family house just before 10:30 a.m., was apparently contained to 57 Murray St.

Richard said that officials were looking into the possibility that the fire was caused by a toddler playing with a lighter.

The entire Lynn Fire Department responded, along with engines from Saugus, Salem, and Swampscott, he said.

“It doesn’t look good. It’s a total loss, I’m sure,” he said.

The building is a two-story, wood-frame built about 1920, according to assessors’ records.