COLORADO SPRINGS ? The Air Force Academy is investigating allegations that one cadet pushed another out a dorm window, causing him to fall 30 feet and break his back, the Colorado Springs school confirmed Wednesday.

The victim’s father, Charles Khan, of St. Louis, said son Nicholas was attacked in March because he had reported the older cadet, who since has graduated, for sexually harassing a female cadet.

Academy spokesman Johnny Whitaker said investigators were trying to determine whether there was evidence to support a charge of aggravated assault in the incident. The name of the former cadet, who now is assigned to Hill Air Force Base in Utah, was not released.

Charles Khan, in a telephone interview Wednesday, said trouble began when his son intervened on behalf of a female freshman who allegedly had been pressured by the senior to have sex. When the female broke off the relationship, the senior blamed cadet Khan.

According to the father’s account: On March 13, the senior came to cadet Khan’s room and told his roommate to leave. Once inside, he saw a written report on the harassment that Khan was preparing and became enraged. He grabbed scissors, ripped out the window screen and called Khan over, telling him someone was calling for him. Then he threw him out the window.