LAKEWOOD, Co. - Authorities in Colorado have identified the police officer who was shot to death Thursday night in an exchange of gunfire with a suspect on a city bus that left four other people hurt.

What we know: Lakewood police identified the officer as 33-year-old Nic Graham, who joined the department of 2019.

Graham's father recently retired from police work while his mother worked in a crime lab, according to Lakewood Police Chief Philip Smith.