Police have released dash cam video of an April traffic stop that led to driving-under-the-influence charges against a Chattanooga man who later went on a shooting rampage that left five servicemen dead.

The video shows Mohamad Youssef Abdulazeez being pulled over on April 20 and undergoing roadside sobriety checks. In the video, Abdulazeez tells officers that white powder on his nose was from snorting powdered caffeine.

On July 16, Abdulazeez opened fire on a recruiting office and then headed across town blast his way through a Navy-Marine reserve center. Four Marines and one sailor lost their lives in the shootings. Abdulazeez was killed in a shootout with police.

A family spokesman called the DUI arrest "important" because Abdulazeez was embarrassed and seemed to sink deeper into depression following that episode.