UNION, S.C. — Prosecutors say they will seek the death penalty against a man accused in the stabbing death of his ex-girlfriend, a South Carolina high school cheerleader.

Pernell Clayton Thompson pleaded not guilty to the charges Monday as prosecutors told him of their decision.

Investigators have said the 20-year-old former Wingate University football player stabbed 16-year-old Marisha Jeter in January to prove his love to his wife.

Jeter's body was discovered under a bridge and her car was found torched in another county.

Jeter was the junior class president, a cheerleader and honor roll student at Union County High School.

Thompson's wife, 19-year-old Yolanda Dee Thompson, has also been charged with murder.

Wingate is a private liberal arts college in North Carolina, about 35 miles east of Charlotte.