CHICAGO (AP) — A 29-year-old Chicago police officer was killed and a second officer was wounded in an exchange of gunfire during a traffic stop, officials said.

The death of the female officer Saturday night was the first fatal shooting of a Chicago officer in the line of duty since 2018.

The two officers were fired upon after they pulled over a vehicle carrying two men and a woman just after 9 p.m. in the South Side neighborhood of West Englewood, according to police.

Chicago police first deputy superintendent Eric Carter told a news conference early Sunday that the officers returned fire and that one of the people in the vehicle also was wounded. That person’s condition was not released.

The female officer died later at the University of Chicago Medical Center, where the other officer was “fighting for his very life,” Carter said.

Two of the people who were in the vehicle were in custody, Carter said. He added that a weapon was also recovered from the scene.

A crowd of officers gathered outside the hospital’s ambulance entrance, some hugging each other and praying. Carter gave the news conference with that gathering as a backdrop, flanked by Mayor Lori Lightfoot.

Lightfoot said the officer who died “was very young on the job, but incredibly enthusiastic to do the work.”

Chicago Police Supt. David Brown gave the female officer’s age in an emailed statement early Sunday but did not identify her.

“The Chicago Police Department has lost one of our own in an incomprehensible act of violence,” he said. “Please pray for the family and loved ones of the fallen officer who will now face a world without her.”

The last Chicago officer shot to death in the line of duty was 28-year-old Samuel Jimenez, who was killed after responding to a shooting at a hospital on Nov. 19, 2018.

Two officers, Conrad Gary and Eduardo Marmolejo, died when they were struck by a train while pursuing a suspect on Dec. 17, 2018. The department also considers the COVID-19 deaths of four officers last year line-of-duty deaths.