VALLEJO (KCBS) –Two people were critically burned when their boat caught fire at the Glen Cove Marina in Vallejo.

The 27-foot pleasure boat caught fire about five p.m. Tuesday and when fire crews arrived, it was fully engulfed in flames, according to Vallejo Fire spokesman Bill Tweedy.

Fire fighters found a man and a woman, in their 50s, who were aboard the boat, suffering from severe burns, Tweedy said.

The man was taken to John Muir Medical Center with third degree burns over nearly 60 percent of his body.  The woman was taken to a local hospital with burns over 45 percent of her body.

Fire crews managed to keep the flames from spreading to nearby boats.

Investigators believe the fire broke out when the man used a lighter to burn off propane gas that he smelled in the cabin of the boat.

The identities of the victims have not been released.