April 19 marks the 23rd anniversary of the Oklahoma City bombing.
On April 19, 1995, Timothy McVeigh and Terry Nichols blew up the Alfred Murrah Federal Building in downtown Oklahoma City with a rental truck packed with homemade explosives.
More than 500 people were injured and 168 people were killed, including 19 children.
It was the deadliest act of domestic terrorism America had ever faced.
