The St. Louis police officer accused of shooting a female officer while playing Russian roulette has allegedly forced other women to play the deadly game, a new lawsuit filed by the dead woman’s mother says.

In the early morning hours of Jan. 24, St. Louis Metropolitan Police Department officers Katlyn Alix, 24, and Nathaniel Hendren, 29, were allegedly drinking and “playing with” a revolver at Hendren’s apartment, a probable cause statement obtained by PEOPLE says.

During the course of the night, Hendren emptied the gun before putting “one cartridge back into the cylinder,” the probable cause statement says.

The two allegedly took turns pointing the gun at each other and pulling the trigger, the probable cause statement says.

At one point, while Hendren was allegedly pointing the gun at Alix, it discharged, striking her in the chest, the probable cause statement says.

RELATED: Cop Accused in Russian Roulette Killing of Colleague Was Allegedly Drinking on Duty: Police

A military veteran and a patrol officer in her second year on the force, Alix was pronounced dead at a local hospital.

Hendren and his partner, Patrick Riordan, who was also at the apartment that night, were both on duty when the shooting took place, the probable cause statement says. Alix was not.

Hendren pleaded not guilty to first-degree manslaughter and armed criminal action and is awaiting trial.

Nathaniel Hendren | St. Louis Police More

He has been suspended from the police department.

On Wednesday, 9 months after the shooting, Alix’s mother Aimee Lynn Wahlers, filed a wrongful death lawsuit in St. Louis Circuit Court against Hendren and others including Riordan, who wasn’t charged in the shooting. Gary Foster, the officers’ sergeant at the time, and the city of St. Louis are also named in the suit, outlets including the Associated Press, the Minneapolis Star-Tribune and local station KMOV.com report.

The suit alleges that Hendren has forced other women to play the game, the AP and the St. Louis Post-Dispatch report.

The lawsuit also alleges Hendren forced past girlfriends to engage in sexual activity that involved firearms, the suit says.

RELATED: Off-Duty St. Louis Officer, 24, Shot and Killed by On-Duty Cop Who ‘Mishandled’ Gun

It alleges that the city should have known that Hendren allegedly had a psychiatric history before hiring him, the St. Louis Post-Dispatch reports.

He has allegedly suffered from anxiety, depression, post-traumatic stress disorder and “suicidal ideations and gestures,” the suit says.

It also alleges that Hendren once put a loaded gun to his mouth and head “just to feel something” when he was alone.

Unlike the probable cause statement, the suit does not state that Alix took part in the game and pointed the gun at Hendren, the AP and the St. Louis Post-Dispatch report.

Nathaniel Hendren walks out of jail after posting 10 percent of $100K bail. Photo via @ColterP_Photo pic.twitter.com/nSF9H602Kd — St. Louis Post-Dispatch (@stltoday) January 31, 2019

It is unclear whether Hendren has hired an attorney to represent him in civil court. His lawyer in the criminal case, Talmage Newton IV, told the St. Louis Post-Dispatch that he wasn’t familiar with the allegations in the suit.

Newton did not immediately respond to PEOPLE’s request for comment.

The city of St. Louis did not immediately respond to a request for comment.