(CNN) — A Michigan man is facing felony charges after DNA from a coffee cup linked him to two rapes in different states from more than 20 years ago, a prosecutor said.

Alan Kurt Rillema, 51, was arrested last week and arraigned in Michigan on charges of first- and second-degree criminal sexual conduct. He also faces felony charges in Pennsylvania, according to court documents.

The charges are the latest stemming from advances in investigative genetic genealogy leading authorities to a suspect in a decades-old cold case.

The first rape Rillema is accused of was reported at a golf course in Michigan in 1999. Someone came in through an employee-only door and sexually assaulted a young woman who was working at the course’s food stand, said Oakland County Sheriff Michael Bouchard at a news conference last week.

Investigators at the time obtained DNA but didn’t have a suspect, the sheriff said.

Then, another rape was reported in 2000 at a golf course at Penn State University, where a woman was attacked while she was jogging and raped at knife point, court documents say.

Investigators in both states, who had submitted DNA samples to a national database, got a match linking the attacks to the same suspect, Bouchard said.

“Now you’ve got people that are victims in different parts of the country with the same kind of M.O., both on a golf course,” the sheriff said.

It wasn’t until years later — thanks to advances in genetic genealogy — that investigators got a lead.

Investigators in both states solicited the help of DNA technology company Parabon NanoLabs, which can use genetic genealogy and other research methods to find suspects using DNA by searching for relatives in public databases and building family trees.

The lab concluded it was likely one of three brothers who were responsible for both rapes, according to Centre County First Assistant District Attorney Sean McGraw.

Authorities were able to narrow the list to Rillema after Michigan police obtained a DNA sample by following him and taking his DNA from a Styrofoam coffee cup, according to McGraw.

“That was sent off to the lab and the DNA taken from the coffee cup matched the DNA of the perpetrator of the 1999 and 2000 rapes,” McGraw told CNN.

Rillema was ordered to be held in a county jail in Michigan without bond until a probable cause conference on Thursday, the Oakland County Sheriff’s Office said.

If convicted of first-degree criminal sexual conduct in Michigan, he could face up to life in prison, the sheriff’s office said.

In Pennsylvania, he faces charges of rape by forcible compulsion, sexual assault, aggravated indecent assault, indecent assault, unlawful restraint, simple assault and recklessly endangering another person, McGraw said.

Rillema has been arraigned and pleaded not guilty, his attorney, Deanna Kelley, said in a statement to CNN. “Regarding the allegations: There are two sides to every story and Mr. Rillema looks forward to telling his,” Kelley said.

Rillema’s next court appearance in Michigan is Thursday. Pennsylvania and Michigan authorities are in the process of discussing the timing of the respective trials, according to McGraw.

Bouchard described Rillema as “an avid golfer” who apparently played all over the US. The sheriff asked anyone who was victim of a similar crime at a golf course to call their local police department.

The arrest was made possible by advances in technology, Bouchard said.

“A lot has changed since 1999,” the sheriff said. “Investigators worked side by side … and found a person that clearly wasn’t on our radar for any reason, has no criminal history, but now has been positively identified in two very violent sexual encounters.”

It isn’t the first time DNA from a coffee cup led investigators to a cold case suspect in Pennsylvania: A man was charged last year with the stabbing death of a 19-year-old woman from 1975 after investigators got his DNA from a cup he used and threw into a trash can at an airport, authorities said.

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