THE CALL came in sounding like hundreds of others that police dispatchers take in this violence-ravaged city:

Person with a gun.

This restraint, known as a "rape stand," was among dogfighting items confiscated Saturday by the PSPCA from a Frankford building. Officials say female dogs are strapped to such stands for mating.

But when officers arrived Saturday night at the sprawling patchwork of rundown businesses in Frankford to investigate, they discovered atrocities they hadn't anticipated.

Seventeen pit bulls, many marked by scars suggesting experience in illegal dogfights, were restrained by short, heavy chains in a fenced lot inside the complex off Adams Avenue near Wingohocking Street.

One dog had a jagged wound down its back that someone had closed with a staple gun. Two pit bulls that had gotten loose were in such a ferocious fight that Pennsylvania SPCA workers later had to euthanize one.

An adjacent building was an animal horror house, filled with tools that dogfighters - called dogmen - typically use to train and breed dogs. A blood-spattered enclosure served as gory testament to the canine carnage that occurred behind the building's grimy stucco walls.

Police are looking for the man they say ran the dogfighting dungeon that sickened even seasoned animal-cruelty investigators.

The grim discovery - the latest in a rash of dogfighting and animal-hoarding cases handled by the PSPCA since August - prompted the organization this week to declare animal cruelty an "epidemic" in Philadelphia.

PSPCA agents have taken in about 100 animals - all suspected victims of illegal dogfighting or hoarders - to its Juniata shelter since August, said the PSPCA's chief executive, Howard Nelson.

"I've been doing this for 16 years, and I've never seen so much of it in my life," said PSPCA Officer George Bengal, an animal-cruelty investigator.

As PSPCA officials pleaded for the public's help in nabbing animal-abusers, police detectives yesterday said they hoped to make an arrest within days. PSPCA agents seized the pit bulls, which are being evaluated by PSPCA veterinarians this week.

The man leasing the site was two months into a three-year lease, Bengal said.

Inside an adjacent one-story building, PSPCA agents found plenty of proof that the pit bulls weren't cuddled as pets.

They found a "rape stand," upon which female dogs are restrained for mating; a treadmill and water tank used to increase dogs' strength and stamina; a medical kit including syringes and a staple gun; and a breaking stick, which dogmen use to pry open a dog's jaws.

Several people working at auto-body shops in the complex yesterday said they had never heard the pit bulls nor seen evidence of dogfighting. The lot where the dogs were held is shielded from prying eyes by a 10-foot wooden fence.

The dogfighting operation was just the latest in a rash of incidents the PSPCA has handled since August:

* Four dead pit bulls were found dumped in two locations in Fairmount Park in August and September. Two more pit-bull bodies were found last month on Enterprise Avenue near the Philadelphia International Airport. Investigators believe that the pit bulls were killed during or after dogfights and were dumped to "hide the evidence." A $3,000 reward - including $2,500 pledged by the Humane Society of the United States - is being offered for information leading to the conviction of the dog-dumpers.

* PSPCA agents have seized almost 80 dogs and cats from animal-hoarders in the last six weeks. In September, the PSPCA removed 17 pit bulls from a moving van rented by an Oxford Circle woman. On Oct. 3, the PSPCA removed more than 60 cats and dogs from a home also in Oxford Circle, in "one of the worst cases we have ever seen," Nelson said. Most of the animals suffered from mange, and the house was filled with animal waste.

PSPCA officials aren't sure why they're seeing more animal- hoarders, but say the trend underscores the need for spaying and neutering pets. Hoarders often suffer from mental illness, added Elaine Skypala, PSPCA chief operating officer.

Skypala speculated that the jump in dogfighting reflects society's growing fascination with violence and blood sports, as well as its obsession with money.

"For some of these people, it's just a badge of honor to have the meanest dog," Skypala said. "For others, it's a way to make a lot of money. If you have a good fighter, you make money not only from the fights they win, but you can then breed that dog and sell the puppies for a lot more money."

Animal-cruelty investigators also often encounter the same hurdle faced by murder detectives daily: Witness intimidation. That makes cracking the cases tougher, enabling dogmen to expand their operations, Bengal said.

"The people engaged in dogfighting 90 percent of the time are also engaged in some other criminal activity, from drugs to guns to gambling," Bengal said. "These are not nice people."