A St. Louis police officer has been charged with involuntary manslaughter after the authorities said he fatally shot another officer during a game of Russian roulette.

The officer, Nathaniel R. Hendren, was charged on Friday in the death of Katlyn Alix, another officer with the St. Louis Metropolitan Police Department.

Officer Hendren had been on duty when he met Officer Alix, who was off duty, at his home on Thursday and the two began playing with guns, according to a statement of probable cause.

Officer Hendren produced a revolver, emptied the cylinder and put one round back in, the statement said. He then spun the cylinder, pointed it away and pulled the trigger. The gun did not fire, the authorities said.