CHICAGO (AP) -- Two men have been charged in the shooting death of a plainclothes Chicago police officer as he investigated reports of gunfire on the South Side, authorities announced Tuesday.
Shawn Gaston, 20, and Kevin Walker, 21, each face charges of first-degree murder, first-degree murder of a peace officer and attempted first-degree murder in Alejandro "Alex" Valadez's death, said Chief of Detectives Thomas Byrne.
It was not immediately clear if Gaston and Walker had attorneys.
Valadez, 27, a three-year veteran who worked in the department's 7th District, was interviewing a citizen about gunfire with his partner early Monday when a vehicle driven by Walker pulled up, Byrne said. Gaston, a passenger, allegedly fired the shots that killed Valadez.
Valadez was struck in the head and the leg and later died at John H. Stroger Jr. Hospital of Cook County.
Gaston and Walker were arrested about an hour after the shooting. They were also responsible for the original gunfire Valadez was investigating, officials said.
Valadez is the third Chicago police officer to die on duty in the past year.
Officer Nathaniel Taylor, 39, a 14-year veteran from the department's Narcotics and Gang Intelligence Unit, was fatally shot in September while serving a search warrant. Officer Richard Francis, 60, a 27-year veteran, was shot and killed in July with his own weapon during a struggle with a woman on a Chicago Transit Authority bus.
Watch the charges being announced: