The mother of a 3-month-old infant called 911 Sunday after what appears to have been a vicious, sustained attack on the child by a family dog.

Twin City Ambulance rushed the baby boy to Women and Children’s Hospital in Buffalo, where doctors performed emergency surgery to replace his intestines. He will then be transferred to the hospital’s intensive care unit.

Officials at the hospital could not release information as to the boy’s condition Sunday.

“While on route, dispatch updated patrols ... that the dogs were being secured and further stated that the child’s stomach had been ripped open,” police reports state.

The child’s mother, 28, called authorities around 1 p.m. after hearing “some noise” and the sound of the infant crying while she was in the shower. She was confronted with a horrific scene — the baby lay screaming in a “penned off” area of the house, barricaded by about 12 feet of safety fence, bleeding profusely from his midsection.

Two dogs, a pit bull and the dog suspected of the attack, a 6-year-old Staffordshire terrier, a member of the pit bull family, reside at the Gath Terrace home.

The terrier was covered in blood. “Based on our investigation, we believe the dog ripped apart a piece of either the gate or fencing and got into the area,” City of Tonawanda Police Detective Tim Toth said.

No charges have been filed in the case. Child Protective Services, however, was contacted because of the victim’s age.

“It doesn’t look like we will be filing any (charges) at this time,” Toth, who deemed the child’s injuries life-threatening, said. “There hasn’t been a criminal aspect to this — it was just an unfortunate accident.”

Reports detail at least three areas of blood in the room, which investigators believe may mean the child was thrown about during the attack.

Toth said by the time police and medical technicians were on hand, an off-duty firefighter who lives around the corner from the residence was already dressing the young male’s wounds.

“There was an off-duty firefighter who I would say probably saved this kid’s life,” he said.

City of Tonawanda Fire Capt. Robert Hassett, 44, said he heard the initial dispatch over a scanner at his home.

He was at the house within a minute of the desperate mother’s call for help.

After that, Hassett said he was able to get past the two dogs at the door with the mother’s help, as she put what is thought to be the attacking dog in the basement while Hassett closed the front door, isolating the second animal on the front porch.

“The baby was crying — which is great — if the baby is crying it’s a great day,” Hassett said.

Hassett, a critical care technician, has undergone years of training, some specific to infant trauma.

It paid off Sunday, as he warmed a bottle of spring water in the family’s microwave to pour over the baby’s exposed wound, described by police as running the length of his torso. Hassett had already administered a tricky I.V. The needle must be plunged into an infant’s bone because their veins are not fully developed.

“Dispatch did a great job,” he said. “She dispatched it out and she said the child had been bitten in the stomach ... I can’t imagine it was easy getting information out of the mom (who was distraught).”

The 18-year veteran of the department credited his role in the matter to the city’s provision of a response vehicle equipped with first aid and paramedic supplies, which he keeps in his driveway when not at work.

“I happened to get there first,” he said, adding another nearby firefighter also heard the call and responded. “But everyone did their job.”

Toth said it did not appear the dog had any reason to attack, and speculated the animal’s territorial instincts may have piqued.

He said in his 18 years on the force, he has never personally dealt with a dog attack “of this magnitude.”

“I don’t know how much a 3-month-old could provoke an animal to do something like this,” Toth said.

City dog control officers and at least two SPCA personnel detained both animals, and no official word has been issued on whether or not either animal will be put down. Ultimately, officials say it is a decision to be made by police, the family or a judge.