A man accidentally shot his coworker Tuesday while showing off his handgun in a south suburban Wendy’s in Alsip.

The 25-year-old Hammond resident removed the magazine from his 9mm handgun before handing what he believed was an unloaded firearm to his coworker, a 17-year-old girl, Alsip police said in a statement.

As the girl handed the gun back to the man, he squeezed the trigger and shot off a round still chambered in the barrel, striking the girl in the leg, police said.

The incident happened about 10:10 p.m. at a Wendy’s at 11110 S. Cicero Ave., police said.

An Oak Lawn police officer arrived shortly after and applied a tourniquet to her leg, according to Oak Lawn Division Chief Ross Finnelly.

The girl was taken to Christ Medical Center in Oak Lawn in serious condition, Alsip police said. Her condition had been stabilized.

Officers reviewed surveillance video of the incident, which led them to find the handgun that was hidden by the man inside the restaurant, police said. He was arrested and the weapon was recovered. Charges are pending.

The officer who applied the tourniquet was exposed to the girl’s blood, and was taken to Christ Medical Center as a precaution, Finnelly said.