According to public safety spokesman Steve McCausland, the bodies of a man and woman were discovered at a home on Fairview Street late Tuesday morning.
McCausland said in a release that the woman died after being rushed to Maine General in Augusta and the man's body was found outside the home.
In the statement, McCausland said the two were an estranged couple in their 40s and did not live in the home where the incident took place.
Investigators say the man shot his wife and then turned the gun on himself.
According to McCausland, their names are being withheld while police work to notify relatives.
McCausland also said the shooting is connected to a house fire in Sidney Tuesday morning, but declined to elaborate on how the two are related.