A 3-year-old boy remains in critical condition at a Boston hospital after a weekend vehicle fire in Franklin.

The boy, whose identity hasn’t been released, was in intensive care with life-threatening injuries at Massachusetts General Hospital in Boston, Shannon Moss, a spokesperson for the Maine Department of Public Safety, said Tuesday afternoon.

The boy was inside the vehicle at a Hog Bay Road home where his parents were working about 3 p.m. Sunday, according to Moss.

His parents don’t live at the Hog Bay Road home.

A fire started in the vehicle, and both parents were injured freeing the boy from the flames, Moss said Monday.

The boy was airlifted to Mass General, while his father was taken to MaineGeneral and his mother to Maine Coast Memorial Hospital in Ellsworth to be treated for burns.

Moss said Tuesday that the Maine fire marshal’s office continues to investigate the fire. No cause has been publicly identified.

No additional information was released.