A Dorchester man who says he looked out his window Monday and spotted a teenage boy hacking a stray cat to death with a machete behind an abandoned home on Mount Everett Street said he was stunned by what he witnessed.

“It was very disturbing,” said Evins Justin of Dorchester, who immediately called the cops. “A person who would do that would do just about anything. He was just having fun cutting it up. Four or five cruisers showed up. He wasn’t even hiding.”

Cops arrested the teen and charged him with two counts of cruelty to animals, possession of a dangerous weapon and trespassing, police said. He was arraigned yesterday in the juvenile session of Dorchester District Court and held pending a dangerousness hearing. Due to his age, his name was not released.

“Officers observed dismembered animal parts in the yard, as well as a machete, handsaw, folding knife, a right hand rubber glove, bottle of Clorox bleach and a black trash bag marked with the defendant’s first name,” according to a statement from Suffolk District Attorney Daniel Conley’s Office.

Neighbors knew something strange was had been going on over there. A large, dilapidated house with one collapsed wall sits on the overgrown lot. The home is boarded and covered in “No Trespassing” signs.

But last week some had spotted a group of three boys walking over there.

An errant football pass sent a 12-year-old girl, her sisters and a 2-year-old neighbor to the abandoned lot last week to track down the ball when the 2-year-old spotted what she thought was a toy — the severed head of a stray cat.

“She wanted to keep it,” said the 12-year-old, who spoke in the presence of her adult caretaker but did not want to be identified for the story. “She thought it was a toy. I told her ‘No.’ Then we saw the body.”

The girl took pictures with her phone that she shared with police. The cat’s body had no head and the paws had been cut off. She said the paws were littered around the large back yard.

The girl said she and her sisters were glad that their own cats — Dora, Sparky and Minny — were OK.