Officer Krystal Rivera was excited to celebrate her daughter's 11th birthday this weekend. But Rivera's life was tragically cut short late Thursday, when she was fatally shot in the back by a bullet fired by another officer.

Police confirmed that the only person who fired a weapon during the chase was an officer, "whose gunfire unintentionally struck Officer Rivera."

Three suspects are in custody after a Chicago police officer was killed in a shooting in the Chatham neighborhood Thursday night, CPD said.Friday morning, authorities identified the slain officer as Krystal Rivera,