A 16-year-old D.C. high school student charged with raping a 34-year-old woman in Georgetown Monday, was at the time free awaiting sentencing in D.C. Superior Court on a charge of assault with a dangerous weapon in an earlier case, according to a statement by a government prosecutor in court.

The youth, who attends Duke Ellington High School for the Performing Arts, was arrested Tuesday and charged in the Georgetown rape. According to D.C. police, the rape victim was choked until she fell unconscious, her head was pounded against a concrete floor by her attacker and she was left for dead.

At a hearing earlier this week in Superior Court where the government sought to have the youth held without bond on the rape charge, Assistant U.S. Attorney Richard W. Goldman said that the youth had been scheduled for sentencing yesterday in the unrelated assault case before Judge Frederick H. Weisberg. According to Goldman, in the assault case, the youth had "pleaded guilty to . . . [a charge of] assault with a dangerous weapon [under] similar circumstances to this [rape] case."

More details concerning the sentencing of the juvenile could not be learned yesterday because a Washington Post reporter assigned to the case was not permitted under D.C. law to attend the proceeding because it involved a juvenile.

The youth was arrested on Tuesday by police after his name was found in books and papers inside a schoolbag dropped near where the woman was attacked in Georgetown.

According to police reports, the woman, who works in an office building near Wisconsin Avenue and K Street NW, was approached by the youth about 2:10 p.m. after she had parked her car in the basement of the building.

According to police, the assailant at first indicated he wanted to rob her. Police said the young man forced her into a stairwell, raped her and then began strangling her with a belt. The assailant let go of the belt and began choking her with his hands, police said, and later her head was pounded against a concrete floor. Other employes in the building found her unconscious shortly afterward and called police.

At the court hearing Tuesday, Judge Robert M. Scott ordered the youth held without bond pending a hearing today on whether he should be further detained while awaiting trial. Unlike the closed hearings on the assault case, the youth is being charged as an adult in the rape case, and the proceedings are expected to be public.