A former Virginia Tech student has pleaded not guilty in the killing of a 13-year-old girl.

Media reports say David Eisenhauer entered his pleas to first-degree murder, abduction and concealing a dead body just before jury selection began Monday in the stabbing death of Nicole Lovell of Blacksburg.

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Prosecutors say the girl climbed out her bedroom window to meet Eisenhauer in 2016 after the two communicated through an instant messaging app. Her body was found three days later.

Eisenhauer, of Columbia, Maryland, admitted meeting her but told police he left when he saw how young she was.

His friend, Natalie Keepers, told police that Eisenhauer killed her to keep her from exposing their inappropriate relationship.

Keepers is charged as an accessory and is scheduled to stand trial in September.