Vicious Dog Attack Leaves 13-Year-Old Boy Dead

March 3, 2014— -- A 13-year-old New Jersey boy was mauled to death in a horrific attack by a 115-pound bull mastiff that got loose and went after the teen and his friend, police reported.

Kenneth Santillan was walking down a street near the Passaic River in Paterson, N.J., Feb. 28 when he and a friend came under attack by a giant bull mastiff that had escaped the fenced yard it was held in, Paterson police said.

Santillan and his friend, also 13, ran in opposite directions to escape the dog. Santillan's friend, whose name has not been released, was able to get away but suffered bite wounds to the hand. He was treated at a local hospital and released.

Santillan's body was found near an icy stream at around 11 p.m. that night, dead apparently from wounds inflicted by the dog. An autopsy is being carried out to determine the cause of his death.

"The exact cause of the boy's death is NOT known at this time. Medical Examiner's Office will be conducting an autopsy and issuing a full report," the Paterson police department said in a statement.

Paul Clarke, who owned the dog, named "Trigger," reportedly stabbed the animal repeatedly during the attack in an attempt to subdue it, suffering bite wounds himself. The dog was later euthanized and its body will be tested for rabies, police said.

No criminal charges have been filed against Clarke.

The dog had been held in its owner's yard within a chain link fence but was able to escape. It was not immediately clear how the dog escaped but it may have jumped over the fence.

Paterson Animal Control Chief John DeCando told ABC News the fence was too short to contain the massive dog. "Look at the size of that dog, and look at the fence," DeCando said. "You tell me how it got out."

Neighbors told the Newark Star Ledger, the dog was kept outdoors even in freezing temperatures and snowstorms and that local boys would occasionally taunt and even throw stones at the dog.

"I noticed, every time he saw a child, he got aggressive," neighbor Zaneia Abraham told the Star Ledger.

Family members have taken to social media to express their grief at the death of the boy.

"Last night, I lost a big part of me, my baby brother, miss you so much already. RIP my angel." Santillan's older sister tweeted.

This is the second fatal dog attack to occur in New Jersey in under a month. Several weeks ago, a 10-year-old boy was attacked by two pit bulls after he was left alone with them in his father's apartment. The victim's 41-year-old father was charged with child endangerment.