A Maryland man pleaded guilty Thursday to kidnapping and sexually assaulting a 10-year-old Pennsylvania girl in 1999 after DNA evidence and fingerprint technology helped solve the decades-old crime.

Timothy D. Nelson Jr., a 50-year-old health insurance analyst, pleaded guilty in Johnstown, Pa. federal court and agreed to a deal which will likely condemn him to 30 years behind bars.

Nelson admitted he abducted the girl in Cairnbrook, Pa., -- about 70 miles southeast of Pittsburgh -- then took her to West Virginia and assaulted her, WJAC-TV reported.

His lawyer, Lyle Dresbold, said Nelson feels remorse and plans to express that at his sentencing next month.

DNA, GENETIC GENEALOGY HELPS EXONERATE AN INNOCENT MAN OF MURDER FOR FIRST TIME

FBI agent Robert Jones told reporters that the child helped investigators recover a discarded paper bag and napkins which eventually linked Nelson to the crime. He said investigators recovered partial latent fingerprints, which matched those of Nelson when they were put through the FBI's Next Generation Identification biometric database last fall.

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"We brought Timothy Nelson Jr. to justice," said U.S. Attorney Scott Brady after the hearing. "And through that, we were able to bring some measure of closure and finality — and yes, freedom — to this courageous young woman."

The Associated Press contributed to this report.