A suspect in a 45-year-old cold case has been moved to Carbon County prison to face homicide charges.

Luis Sierra, of Ozone Park, New York, is accused of the murder of a pregnant teenage girl whose remains were found in 1976 beneath the Interstate 80 bridge over the Lehigh River.

A recent DNA match led to the identification of the victim, who was known for many years only as “Beth Doe”. But last year police learned that she was Evelyn Colon, a 15-year-old girl who went missing in 1976.

“The Pennsylvania State Police has never stopped working on this case, as we do with all our cases. Each victim does matter to us, and we’ll take all appropriate measures and actions to bring a case to a conclusion,” state police Lt. Devon Brutosky said.

Police and prosecutors are still determining whether to file additional charges against Sierra. Pennsylvania’s fetal homicide law wasn’t in effect at the time of the murder.

District Attorney Michael Greek said his office and state police have not made a decision on whether to seek the death penalty against Sierra.

The victim’s remains found by a local teenager in 1976. She died of strangulation, though she was also shot in the neck, according to coroner reports.

More than 100 troopers worked on moving the case over the ensuing decades, including creating a DNA profile in 2007.

Ultimately the big break in the case came when a relative of Colon’s participated in an ancestry DNA test.

The relative’s DNA profile matched the unidentified victim’s, which had recently been cross referenced with the ancestry DNA database.

Once police identified her as Colon, family members pointed them to her then-boyfriend, Sierra.

Family members said they had received a letter from Colon following her disappearance which said she had given birth to her baby and named it Luis Sierra Jr.

Sierra was charged by Pennsylvania State Police after they interviewed him at his home in Ozone Park, NY. He had been working as a bus driver.

Troopers said her family was happy to have some closure, but also disturbed by the details of the case.

The ability to compare the DNA of unidentified victims with ancestry databases wasn’t available until recently.

“I believe it’s a very bright future for that. It’s the future of what we are doing to solve cold cases,” Brutosky said.

He added that state police were happy to have closed a case which has been open since before many currently on the force were born.

Greek commended the past and present troopers of the Troop N criminal investigation unit who worked the case over the past 44 years.

“Their hard work and perseverance made the identification of Evelyn Colon and her daughter possible, and brought at least some level of closure to her family to what was a tragic and longstanding mystery,” Greek said.

Greek encouraged anyone with information about the case to call the state police tip line, 1-800-4PA-TIPS, with reference no. 1956.

Sierra is being held without bail, awaiting a preliminary hearing scheduled for April 28.