How Slain Jogger’s Fight Against Her Killer Helped Police Identify a Suspect 6 Months Later

N.Y.C. Jogger Slain in 'Crime of Opportunity': Prosecutor

As the life was being choked from her body six months ago, Karina Vetrano fought fiercely against her killer — clawing at his skin with her nails and biting him with such force that her teeth cracked, authorities say.

Detectives are glad she did.

This weekend, New York City police detained 20-year-old Chanel Lewis and charged him with murder and sexual assault in connection with Vetrano’s brutal killing on Aug. 2, 2016, in a Queens park. But police say the arrest may never have happened if not for Vetrano’s actions in her final moments.

Several tiny shreds of the killer’s skin were recovered from beneath her fingernails, New York City’s Chief of Detectives Robert Boyce explained at a Sunday news conference. It was this DNA evidence that eventually led to Lewis.

“Karina helped us identify this person,” Boyce told reporters. “She had the DNA under her nails. She had touch DNA on her back and there was more DNA on her cellphone. That’s how we were able to bring this profile up, and that’s how we made the link. This is a very good day for justice in New York City.”

Vetrano’s battered body was discovered face-down in the park within hours of her killing. She was found not far from a running path she jogged daily, and she was last seen by her family heading out to run.

Police say she was beaten and sexually assaulted before being strangled to death. There was a clump of grass in one of her hands, indicating she was dragged into the weeds where she was eventually killed.

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Investigators began developing a profile on Lewis two weeks ago, after discovering he had been issued several summonses near the crime scene in the days before Vetrano’s killing, Boyce said on Sunday. They tracked him to his mother’s house. On Thursday, he gave investigators a DNA sample, which was matched on Saturday to a sample recovered from Vetrano’s body, leading to his arrest.

An N.Y.C. police source tells PEOPLE that Lewis expressed a hatred for women as he was being interviewed in custody. Detectives have also learned that he had allegedly threatened to hurt female students at his high school with a knife.

The source adds that investigators do not know what sparked Lewis’ apparent misogyny, but he allegedly told investigators he couldn’t stop himself from attacking Vetrano as she jogged passed him.

Police say hospital records from early August also confirm that around the time Vetrano was killed, Lewis was treated for an injury to one of his hands. (He told doctors he had been mugged by three men.)

Lewis has yet to enter a plea to the charges against him. Messages left for his parents and lawyers were not returned Monday. Vetrano’s parents were also unavailable for comment.

Lewis was arraigned on Sunday and held with bail, according to local reports. Vetrano’s family, including her parents, attended the hearing and Vetrano’s mother chastised Lewis as he left the court, according to CBS New York.

“Savage murderer!” she called out, according to the station. “He murdered my daughter — my beautiful, innocent daughter!”

“He’s a demon!” she said. “He’s a demon!”

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Lewis’ father did previously told the New York Post his son’s arrest was “extremely surprising.” He said his son is a “humble” young man who excelled in school.

“Chanel would never have gone to do what they say he has done,” his father said. “He’s never had a fight in his 20 years.”

Lewis is due back in court on Feb. 21, according to the Queens District Attorney’s office.