Chicago police Officer Krystal Rivera was mistakenly shot and killed by a fellow cop during a confrontation with an armed suspect late Thursday, according to police, who continue to hold at least

Chicago police are investigating how a police officer was shot and killed while conducting an investigatory stop in Chatham Thursday night.

Earlier in what would be her final shift, Chicago police Officer Krystal Rivera took two guns off the street, authorities said, only to come face-to-face with a rifle later that night. Rivera, 36, a four-year veteran with a young daughter who lived in the Irving Park neighborhood on the Northwest Side,