MARLBOROUGH, Mass. (WHDH) -- Officials are investigating after a Marlborough police officer fatally shot a man while responding to a domestic disturbance call.

Authorities say police responded to a Meadow Brook Road address at about 8 p.m. Monday to assist in the removal of an unwanted person from a home.

The district attorney says responding officers were confronted by a man with a knife. A Marlborough police officer opened fired killing 22-year-old Bryce Coutinho.

Coutinho's friend said he was a good person.

"He'll be always in my heart. And I'll always be thinking about my friend," said Timal Patel. "It was just hard to accept the news that he's not here anymore."

“Very upset someone died like this across the street, just terrible,” said George Every, a neighbor. “It’s a terrible shame. So awful.”

Neighbors on the street were shocked to hear an officer shot and killed the young man.

“Police were everywhere. State troopers they has the suits on, taking pictures of everything,” said Ben Gerber.

Investigators could be seen going in and out of the home. They focused their attention on a room on the second floor.

“It probably occurred on the second floor. Everything went in the front door and up the stairs,” said Every.

Neighbors said they didn’t hear gun shots, but suddenly there were more than a dozen police cars and officers at the home.

Neighbors said the occupants have only lived there for about a year. They said a couple, an adult woman and the young man who was killed, just started staying there a few months ago.

Coutinho was arrested at the home last week for a warrant of domestic assault and battery.

The District Attorney’s office is not releasing the name of the officer who shot the man.