Man arrested in 1991 cold case killing of 16-year-old girl after he's linked by DNA: Sheriff Sarah Yarborough, 16, was found dead in bushes outside a school in 1991.

Twenty-eight years after a 16-year-old girl was found slain outside her Washington state high school, a man is now in custody, linked by DNA to the crime, authorities say.

Patrick Nicholas, now 55, is accused of killing Sarah Yarborough on Dec. 14, 1991, when she arrived at her high school in Federal Way, just outside of Tacoma, on an early Saturday morning to meet her drill team, King County Sheriff Mitzi Johanknecht said.

Yarborough was beaten and strangled to death with her stockings, according to court documents. Nicholas was 27 at the time, according to documents.

A man jogging that morning noticed a girl lying motionless on the ground and a man kneeling over her, according to court documents. But the jogger thought, "they were a couple 'making out' and jogged on," according to documents.

Just after 9 a.m., two 12-year-old boys saw a man emerge from the bushy hillside near the school; after the man walked away, the boys looked by the hillside and saw the teen's body, dressed in a drill team uniform, documents said.

While semen was discovered on the teen's clothes at the crime scene, and the DNA profile was searched regularly in state and national DNA databases, no match was made for decades, according to documents.

Last week, genealogists working on the case zeroed in on two brothers identified through the novel investigative technique known as genetic genealogy, which uses an unknown suspect's DNA to trace his or her family tree.

One of the brothers identified by the genealogists was ruled out, because he had a prior rape conviction and his DNA was in CODIS -- and the DNA wasn't a match, according to court documents.

The second brother was Patrick Nicholas. He had served time in prison for an attempted rape from 1983, but his DNA was never entered into CODIS, according to the court documents.

Patrick Nicholas had also been arrested in 1993 for child molestation for which he pleaded guilty to a fourth-degree charge of gross misdemeanor assault, according to court documents.

This weekend investigators surveilled 55-year-old Nicholas and collected a cigarette that he'd tossed on the ground, court documents said.

The cigarette was sent for testing, and investigators learned Wednesday that the DNA from the cigarette matched the DNA on Yarborough's clothes, documents said.

Nicholas was taken into custody Wednesday night for first-degree murder, authorities said.

Almost 4,000 tips had been submitted in the Yarborough case by the time of the arrest -- but none of the tips identified Nicholas, King County Sheriff's Detective Kathleen Decker said at a Thursday news conference.

If you're going to do something heinous, don't do it here. Because they'll come to get you.

There's no apparent connection between Nicholas and Yarborough, Decker said.

The prosecution says Nicholas will have an arraignment hearing on Oct. 17. No defense attorney is assigned to him yet.

Sarah Yarborough's mother, Laura Yarborough, spoke at a news conference on Thursday where the arrest was announced, and she called her slain daughter an excellent student, who always had a book in her hand. The teen was excited for college, with big hopes and dreams for her future, her mother said.

The sheriff said, "few things in law enforcement are more rewarding than telling a parent that you believe you have solved the murder of their child."

Laura Yarborough said even when she gave up at times, the detectives never did.

"If you're going to do something heinous, don't do it here. Because they'll come to get you," Laura Yarborough said.