A Mount Rainier police officer was indicted Tuesday by a Prince George’s County grand jury on attempted murder and sex-offense charges after a July 2 shooting in Capitol Heights, the state’s attorney’s office said. The officer, who was off-duty at the time, maintained that he had been carjacked.

A 12-count indictment alleges that Gene Gillette, 27, shot a man in the 700 block of Glacier Avenue after assaulting him, touching his genitals and trying to sexually assault him, officials said in a statement.

Two law enforcement sources said that the altercation happened over an attempted sexual encounter in Gillette’s house and that the officer shot the victim as he tried to flee in Gillette’s car. The sources said Gillette lured the victim to the home with a promise of making a pornographic movie with women, but no women were at the house.

Gillette turned himself in to Prince George’s police Tuesday night. Gillette was placed on suspension without pay, and his police powers were revoked, Mount Rainier Police Chief Michael Scott said.

Gillette won top honors from the department. He was named Rookie of the Year in 2008 and Officer of the Year in 2009 and 2010, according to reports by Scott. Gillette also led the department in making criminal arrests and issuing traffic citations in 2010.

The condition of the shooting victim was not immediately clear.

Staff Writer Justin Jouvenal contributed to this report.