A Dorchester woman is grieving the savage death of a beloved elderly mixed breed pooch named Chopper, while struggling to understand why he was killed by two other dogs that were also treated as members of her family.

Mother-and-son pit bulls Coco and Hannibal were euthanized in the aftermath of Monday’s bloodbath on Mascot Street, which included an attack on the right arm of an animal control officer. Lisa Timberlake, spokeswoman for Boston’s Animal Care and Control, told the Herald the pair were put down “due to their aggressive behavior and the danger it posed to the public.”

The officer, she said, was treated at Brigham and Women’s Hospital and “is at home and resting comfortably.”

“Total shock,” Mona Fuller, 47, said after Chopper, 14, died at home early yesterday morning after his horrifically mauled throat had been stitched up.

Coco and Hannibal, who belonged to a relative and shared the house, didn’t seem fond of Chopper, but “never displayed any kind of vicious behavior,” said Fuller, still hoarse more than 24 hours after she’d screamed for help.

Fuller said she was between running errands and a dentist appointment shortly before noon Monday when she let Chopper out in the fenced-in backyard unattended because there was no indication Coco and Hannibal were loose, as well.

She was grabbing her purse and about to call the “easy going” Chopper in when she saw Coco and Hannibal, jaws clamped on his neck, drag him from the bottom of the stairs, across the yard.

“I was yelling and yelling, ‘Somebody help me, they’re killing my dog!’ ” Fuller told the Herald.

She called her son home from work and tried assailing the pit bulls with bottles her mom had set aside for recycling, but she said, “They were just on him the whole time.”

When her son arrived, Fuller said he grabbed a rake and charged Coco and Hannibal, swinging. “He just started whacking them, whacking them,” she said, adding the rake snapped in two and the dogs tried to turn on him when he dove in to rescue Chopper.

Meanwhile, she said, Boston police arriving on scene were able to safely corner the pit bulls with two barbecue grills. Police said one officer even applied pressure to Chopper’s neck to try to stem the blood loss.

Fuller said the family is grateful for the brief time they shared with Chopper to say their goodbyes.

“He made it to his final destination,” she said with a bittersweet smile. “He was in a good place.”