A Chicago man accused of sexually assaulting his ex-girlfriend and injuring a university police officer who tried to help her has been ordered held on $800,000 bond.

A Cook County judge charged Diego Rodriguez, 20, on Monday with felony counts including aggravated criminal sexual assault, aggravated battery to a police officer and aggravated domestic battery or strangulation.

An off-duty University of Illinois at Chicago officer saw Rodriguez forcing a 19-year-old woman into his vehicle in an alley early Sunday in Chicago's Norwood Park neighborhood, prosecutors said. The officer tried to pull the woman out of the car but Rodriguez sped away, dragging the officer. The victim was thrown from the moving vehicle nearby.

Rodriguez had sexually assaulted the victim before the officer saw them, Assistant State's Attorney Beth Novy said. He stabbed her with scissors as she tried to break free after spotting the officer, she said.

The victim and officer were taken to a hospital with non-life-threatening injuries, police said. Police arrested Rodriguez later that day.

It wasn't immediately available if he has an attorney.