He died a short time later while waiting in an ambulance for a medical helicopter to arrive.
State police spokesman Stephen McCausland says police responded to a domestic assault call on Main Street at around 8:30 pm. Neighbors told TV5 Monday night that they heard gunshots about an hour earlier.
At the scene, officers encountered John Sullivan, whom they say was armed with a shotgun.
Sullivan had reportedly assaulted a woman inside the residence.
Police sealed off a section of Main Street for part of Monday night.
McCausland says the attorney general’s office is now in charge of the investigation, which is standard procedure when any officer is involved in a shooting.