By Jennifer McRae

LITTLETON, Colo. (CBS4)– Tuesday marks a dark day in Colorado history. Twelve students and a teacher at Columbine High School were killed on April 20, 1999.

Coloradans remember the tragedy on this day and honor the lives of those killed and injured.

READ MORE: Police: Man Kills 6 Adults & Himself At Colorado Springs Birthday Party

MORE NEWS: $30,000 Reward Now Offered In 1970 Murder Of Marilee Burt

(credit: CBS)

Cassie Bernall
Steven Curnow
Corey DePooter
Kelly Fleming
Matthew Kechter
Daniel Mauser
Daniel Rohrbough
Dave Sanders
Rachel Scott
Isaiah Shoels
John Tomlin
Lauren Townsend
Kyle Velasquez

Jennifer McRae