DNA evidence lifted from a discarded cigarette led Florida police to the man they believe killed a young mother 35 years ago, authorities said Thursday.

Tonya Ethridge McKinley, then 23, had just left a New Year’s Eve celebration before she was strangled and sexually assaulted in Pensacola, allegedly by Daniel Leonard Wells, now 57, according to police.

Detectives said they spoke to dozens of friends and other revelers at Darryl’s Bar & Grille, not far from where McKinley was found on Jan. 1, 1985. But for most of this time, they had no suspect in the killing of McKinley, who was survived by an 18-month-old son.

“Despite having a good bit of physical evidence and dozens of interviews, over time, the trail went cold,” according to a police statement on Thursday. “It seems that every couple of years a new lead would pop up and we would drop everything to run it down. We did this time and time again. In the meantime, a baby boy grew up without a mother, parents buried their daughter without knowing justice, and a killer was walking around free. “

But DNA in a public database linked detectives to distant relatives of McKinley’s killer and eventually to Wells, police said. Detectives eventually suspected Wells and they secretly followed him before collecting a cigarette he threw away — matching DNA off that butt to DNA found at the crime scene.

“Each time, evil won, just out of reach,” police said of the 35-year gap. “Until today. Today, the evil that took Tonya from her friends and family was arrested for her brutal murder.”

Wells’ DNA is being offered to other nearby law enforcement with unsolved sex crimes, because he’s lived locally this whole time, Pensacola police spokesman Mike Wood said.

“The reasons why this happened, how evil crossed Tonya’s path, may never be answered and in the end may not be important,” according to police. “What is important is that no one forgot Tonya. “

Wells was booked into the Escambia County Jail on Wednesday and held without bail. He’s been charged with murder and sexual battery.

It wasn’t immediately clear if Wells had hired or been assigned an attorney, Wood said Thursday.