MEMPHIS, Tenn. (WREG) — A Cordova, Tennessee teen pleaded guilty to beating and abusing three children he was babysitting in 2015, and one of the children died from her injuries.

Antonio Evans, now 18, was convicted of second-degree murder, aggravated child abuse and aggravated child abuse of a child under age 8. He was sentenced to 30 years in prison, according to a release from district attorney Amy Weirich.

Evans, who was 14 at the time, was left in charge of three children — aged 6,7 and 9 — in December 2015. The children were being fostered by a Cordova woman who lived at a home on Beaver Trail. Evans was a foster child of the woman’s daughter and lived a different house, the district attorney said.

During the third day Evans was babysitting, police were called as the 6-year-old began throwing up and was unresponsive. She was hospitalized in extremely critical condition and died from the injuries five days later.

Investigators found that she and her two siblings were beaten and abused over a three-day period by Evans. They said Evans punched, kicked, slapped and whipped the children with a cord and a belt.

The children said Evans threatened them with more abuse if they told anyone.