North Carolina cold case detectives have arrested the mother of a newborn who died after being tossed from a moving car 21 years ago this month.

Authorities said they linked Deborah Riddle O’Connor, 54, to “Baby Michael” after submitting the infant’s DNA to a lab that specializes in genetic genealogy testing.

Her arrest for first-degree murder was announced Thursday by Cumberland County Sheriff Ennis Wright.

“Detectives have never given up working on this homicide, and finally got a break in the case,” Wright said.

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Wright said the investigation began March 3, 1999, with the discovery of a plastic trash bag by a soldier who was driving by and thought he saw a doll inside.

“Inside the bag was no doll, instead it was a baby boy not even 24 hours old, his umbilical cord still attached,” the sheriff said.

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The baby died of blunt force trauma after being tossed from a vehicle, authorities said.

Detectives said O’Connor was living in another county, 200 miles away from where the baby was found.

She admitted being the baby’s mother during an interview with detectives, Wright said.

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O'Conner was jailed after her arrest and is due in court Friday.