Police are looking for 52-year-old Denis Bisson of Berlin, New Hampshire.
He's 5'6", weighs about 170 pounds and has brown hair and brown eyes.
Authorities say Bisson is driving a silver 2015 Toyota Tundra with a New Hampshire license plate with the letters "ALL GD."
Maine police are coordinating with New Hampshire authorities who say Bisson is wanted in connection with the death of his wife.
Authorities believe he may be in the Rumford or Mexico, ME, area and should be considered armed and dangerous.
A command post is currently set up at Rumford High School and dozens of Maine officers are assisting in the search.
There are also helicopters flying overhead in the area of Somerset Street in Rumford.
Police say there have been no confirmed sightings of Bisson so far.
Anyone with information about Bisson, his truck or where he might be should call Maine State Police in Augusta at 624-7076.