In Prince George’s County, Maryland, DNA technology has helped investigators find the man responsible for the 2017 murder of 26-year-old Matthew Mickens-Murray.

On Tuesday, Brandon Biagas, 23, of Waldorf, pleaded guilty to second-degree murder in the death of Mickens-Murray, who was found stabbed to death by police in his apartment along Newton Street in unincorporated Hyattsville.

Biagas was sentenced to 30 years; he’ll serve 17 years, and could still serve the other 13 years if he violates probation once released.

It’s the first time the county has used forensic genetic genealogy to solve a cold case.

“This is a very significant case and we are pleased with the outcome,” said State’s Attorney Aisha Braveboy.

Braveboy’s office said in a statement that investigators found DNA and fingerprints at the crime scene that they couldn’t identify. Local and national databases didn’t turn up any matches, either; the samples were then sent to a lab for forensic genetic genealogy analysis, which made a connection with relatives of Biagas.

Police then found that Biagas and Mickens-Murray had been in contact through a dating site, and that Biagas had checked himself in to a medical center the night of the killing with a cut on his hand. DNA analysis connected him with the crime scene from there.

The use of genealogy in future cases is being made possible by a $470,000 grant from the Department of Justice, and Braveboy said they will continue to seek resources outside of the grant in an effort to keep the technology funded. Her office was one of 10 across the nation to receive the financial assistance.

“We want to send a very strong message that no matter how old the case, we will continue to pursue it,” said Braveboy. “For those who have lost their lives, this is the way that we honor them, by using everything in our power, using all the tools that we can.”

“We have several dozen [cases] that are waiting,” said Assistant State’s Attorney Robert Dean. “This is a breakthrough.”