SHELBY, Ohio (WTVN) -- Police in northern Ohio say a 17-year-old girl told officers that she was the one who gave birth to a baby whose remains were found in the trunk of a car at a repair shop.

Shelby Police Chief Charlie Roub said the girl told investigators Tuesday night that she didn't know she was pregnant and gave birth at home in late January or early February.

The vehicle had been dropped off on Friday, but picked back up over the weekend. It was returned on Tuesday.

"The mechanic was working on it, smelled an odor in the vehicle and thought maybe an animal had gotten in the car and started looking for that," said Roub.

The mechanic discovered the smell was coming from a copy paper box in the trunk and started to throw it away when he looked inside.

"It was not an animal that was in there it was in fact an infant," he said.

Police are hoping to learn more after an autopsy is completed. He says they don't know at this point whether or not the baby was alive when it was born.

"We have some more questions as far as that goes, but she didn't indicate that the baby cried or moved or anything," said Roub.

The girl is a local resident who has not been taken into custody.