Background: News footage of the home where Andrew Horsman allegedly stabbed his mother’s boyfriend (WBZ). Inset: Paul Pomerleau (Provided by family).

A Massachusetts man allegedly stabbed his mother’s longtime boyfriend after a feud culminated in a violent altercation, according to family members of the alleged victim.

The Middleborough Police Department announced the arrest of Andrew Horsman, 41, and charged him with the murder of 66-year-old Paul Pomerleau. In a press release, police said that officers responded to multiple 911 calls placed at around 8 p.m. on Sunday night reporting a fight in a suburban Middleborough neighborhood. They arrived to find Pomerleau suffering from “multiple stab wounds” and immediately transported him to a nearby hospital where he was pronounced dead.

Horsman’s mother was in a long-term relationship with Pomerleau, and family told local news outlets that the two men had been engaged in a feud.

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According to police, Horsman and Pomerleau were having an argument in the moments leading up to the alleged stabbing. Police said there were several witnesses to the argument, and family members told local ABC affiliate WCBV that there had been a longtime feud between Horsman and his mother’s boyfriend that reached a head over the weekend.

Local CBS affiliate spoke to Jeff Burr, a neighbor who said he knew Pomerleau for “30 years” and told the outlet, “I’ll tell you, he was like a gentle giant. He was a great guy. He’d give you the shirt off his back. You know, he really would.”