TULSA, Oklahoma - A Tulsa woman was sentenced to 40 years in prison after pleading guilty to child abuse murder. Ashley Ledbetter admitted to fatally injuring her 3-month-old son Zion last summer, according to child crisis detectives.

Police said Ledbetter first told them she left the room and came back to find her son on the floor unresponsive. She later admitted to getting upset about the baby crying and tied a blanket around his head to hold a pacifier in his mouth, records show.

When that didn't work, police say she slammed him five times, face down on the bed. At one point, investigators say Zion bounced into a dresser, hitting his head.

“Numerous injuries. All of them were very severe,” said Detective Matthew Snow with the Child Crisis Unit.

"Traumatic injuries to the head, had numerous skull fractures, had a lacerated liver, had a lacerated spine."

Ledbetter waived her right to a jury trial. After serving the 40-year sentence, she will be on probation for the rest of her life, according to court documents.