By Louisa Moller, WBZ-TV

BROCKTON (CBS) — A 71-year-old man was the victim of a home invasion Wednesday night, when three masked men strung him up inside his home and repeatedly shocked him with a stun gun, police say.

Mike Acciavatti is hospitalized undergoing surgery on his hip after being tied up with his own suspenders and left by the robbers, waiting for hours before he got free and called police. The robbers allegedly asked Acciavatti for gold. Friends say he collected gold coins, but not enough for anyone to try to rob him.

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“I’m kind of scared,” one friend said, “for something to happen to him and he doesn’t do anything.”

Police say a Brockton man was tied up and shocked with a Taser during a home invasion. (WBZ-TV)

Police say a Brockton man was tied up and shocked with a Taser during a home invasion. (WBZ-TV)

The attack is sad, neighbors said, because Acciavatti is such a nice guy, known for sitting in a chair near his front door when the weather is nice.

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“He’s a very nice guy, I really like him. He’s really a great guy,” one neighbor said.

“He would watch all of us,” another neighbor added. “It’s sad because something happened to him and we don’t know who did it.”

According to friends, Acciavatti spent a lot of time at Supreme Coffee and Donuts with a group of men. They described him as a collector and antique enthusiast.

“I don’t think he has gold. He had coins, he had a lot of coins. A lot of watches, clocks, things like that,” friend Rocky Savino said.

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Acciavatti’s attackers are still on the loose.