DENVER, CO (WCMH) — A teenage mother is accused of smothering her newborn child with a rock.

According to KDVR, the newborn was found behind homes in Green Valley Ranch in September.

Police say the 16-year-old mother, Alaya Dotson, told them she didn’t know she was pregnant, and took the newborn to the backyard of a home after a surprise delivery.

Dotson told police she put a rock inside the baby’s mouth and pushing it down the throat of the child, according to an affidavit.

Dotson is facing first degree murder charges and is being tried as an adult.