Maine State Fire Marshal's said Fred Roberts, 65, was arrested Wednesday afternoon.
Investigators stated he poured gasoline inside his house this morning and set it ablaze while his longtime companion was upstairs.
Barbara King, 70, said she awoke and saw a flash of fire, but was unable to get downstairs because of the flames. She escaped by jumping from a second floor window.
She's now being treated for various injuries.
The house on the Hudson Road was flattened by the fire and Roberts was located walking along a roadway as fire crews arrived on the scene.
No word on a motive for the alleged arson.