"I heard someone whimpering, yelling for help," Andrew Sims told the Detroit Free Press.
When the Vietnam vet got closer to the sound, he got his first glimpse of the gut-wrenching sight.
"I couldn't see him," Sims told the Free Press. "All I could see was a pack of dogs. … They didn't stop. I could just see them tugging, you know, pulling at him."
So vicious were the dogs that emergency workers had to remain in their vehicle until police arrived and started shooting them, Sims told the paper.
"When we found the victim he was lying in a yard, completely naked, being attacked by several pit bulls,” Sgt. Michael Woody told WWJ-TV, “and our officers had to try to corral the pit bulls.”
The unidentified victim's hands and feet were "chewed off" in Thursday's attack, Detective Michael Pacteles added to the Free Press.
At least one dog was fatally shot, the paper said, and officers lured the others back into the house from where they escaped presumably from a side door.
Woody told the Free Press that all 12 dogs that had been in the house, including four puppies, took part in the attack — and none was licensed.
"Because of the viciousness of the attack, the remaining pit bulls will be euthanized," Woody told the paper, noting that all would be tested for rabies.
More from the Free Press:
Police have been unable to identify the injured man, who is believed to be 40 to 50 years old. He was taken to Detroit Receiving Hospital after the attack, where he was listed in critical condition, but he has been unconscious because of his injuries, Woody said, noting that he lost a lot of blood.
The man could speak, barely, when police and emergency workers got to him, but he was unable to provide his name. It's unclear why he was naked or if the dogs had ripped his clothes off, and it's unclear what led to the attack or why the man was in the area.
Detective Pacteles said the dogs that were seized Friday were thin and looked malnourished. He called the condition of the home, which had ample clutter visible through an open front door, "deplorable. ... I took one step in and it smelled pretty bad."
The Free Press reported that the dogs' owner, identified by a family member as Derrick Felton, wasn't home during the attack but was escorted away Friday morning by police. Woody told the paper that he could face felony charges, including harboring vicious animals, but noted to WWJ that investigators don't believe he's involved in dog fighting.