Teen William Riley Gaul out on $1.34 million bail for ex Emma Walker's murder

William Riley Gaul and Emma Jane Walker. Photo / Twitter

A former university footballer who allegedly stalked and killed his cheerleader girlfriend has been released from jail on $US1 million bail ($1.34m).

The New York Daily News reports that William Riley Gaul, 18, was discharged from the Knox County Detention Facility in Tennessee after posting the bail.

William Riley Gaul and Emma Jane Walker went to prom together. Photo / Twitter

Gaul was arrested on November 22 a day after it is alleged that he took his grandfather's gun to shoot his ex-girlfriend, Emma Walker, 16, in her bedroom.

Before his arrest he tweeted about his love for his dead ex.

"I love you Emma, I can't be around any of that yet, it's too soon. I know you know I'm dying to be there but understand I can't. I love you."

Walker's aunt Jenny Weldon said her niece had "chosen to move on" and that he "refused to accept it."

Gaul is being required to wear a GPS monitoring bracelet while out on bail.

His criminal proceeds hearing will take place on February 13.