Jan. 25 (UPI) -- A St. Louis police officer was killed when another officer "mishandled" a gun and shot her, authorities said Thursday.
Officer Katlyn Alix, 24, was off-duty when she was shot in the chest by a patrolling officer early Thursday in the living room of a Carondelet neighborhood apartment. Another on-duty officer was also at the home.
Police Chief John Hayden said Alix was shot when the weapon was accidentally discharged, the St. Louis Post-Dispatch reported.
One of the two male officers lived at the apartment, the Post-Dispatch reported, adding that the reason they were at the residence while on-duty is unknown.
Alix was sitting in the living room when one of the officers "mishandled a firearm" and shot her in the chest, police spokeswoman Officer Michelle Woodling told CNN.
Following the shooting, the two on-duty officers, both described as 29-year-old white men, rushed Alix to St. Louis University Hospital, where she died shortly after arrival.
The St. Louis Circuit Attorney's Office said it's opened a criminal investigation and a prosecutor and two investigators had already been to the scene.
"This is a tragic situation," St. Louis Circuit Attorney Kimberly M. Gardner said. "The family of officer Alix deserves a complete, objective and thorough investigation of this incident. My office is approaching this criminal investigation with the highest level of seriousness and urgency."
A CAO prosecutor and two investigators responded to the officer-involved shooting scene this morning. We have opened an investigation into the matter.— Circuit Attorney (@stlcao) January 24, 2019
She also said she's asked the Missouri State Highway Patrol to assist in the investigation. The police department's Force Investigation Unit is also investigating, CNN reported.
"Officer Alix was an enthusiastic and energetic young woman with a bright future ahead of her," Chief Hayden said in a statement.
Alix had two years of experience on the force. The St. Louis police department said its officers will wear department mourning bands to honor Alix.