Three firefighters were treated for minor injuries March 20 at an out of control grass fire in South Thomaston.

During the early afternoon, Mike and Joanna Monroe were conducting a permitted grass fire on their property at 422 Spruce Head Road, according to Fire Chief Brian Calderwood. The wind picked up and the fire got out of control.

The fire spread through a marsh up to Waterman Beach Road. Calderwood said the grass on top of the marsh was dry.

Mutual aid was called for and firefighters from South Thomaston, Thomaston, St. George and Owls Head worked at the blaze. Calderwood said a total of about 50 firefighters worked at the scene.

Three firefighters suffered minor injuries. Two were treated for minor burns and one was treated for exhaustion by the South Thomaston Ambulance Service.

Calderwood said that since the fire was deep in the marsh, there was no way to bring trucks in to fight the fire. Firefighters had to carry Indian tanks filled with water into the muddy marsh and fight the blaze that way.

“The wind was against us,” Calderwood said.

The fire was mostly under control by about 4 p.m. The Maine Forest Service also responded.