Fire engulfs Watertown building

WATERTOWN, Mass. (WHDH) -- A large fire broke out at a building on Main Street in Watertown Tuesday night.

Neighbors told 7News the building contains a yoga studio, an insurance company, and a hair salon. They said they saw smoke billowing out from the structure and then heard a loud explosion.

Witnesses said they believe the fire came from the hair salon in the back of the building.

Firefighters contained the fire late Tuesday night.

The cause of the fire is under investigation.