Chattanooga Gunman Was Avid Cage Fighter, Practiced Martial Arts, Blogged Before Death: 'Life Is Short and Bitter'

Intriguing new details are emerging about the domestic terrorist who killed four Marines in Chattanooga.

Bullet holes could be seen at a Marine recruiting office, where the first of the two shootings took place. The crazed gunman, Mohammad Youssef Abdulazeez, was born in Kuwait, but moved to the U.S. with his family when he was five.

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Here he lived an all-American life. He would visit a Tennessee swimming hole with friends. In high school, he looked like any other student - in his senior year yearbook, he even wore a tuxedo.

But, ominously, his yearbook quote was: "My name causes national security alerts. What does yours do?"

Abdulazeez was a mixed martial arts fighter. There's an eerie similarity between this photo and Boston bomber Tamerlan Tsarnaev, who was also into martial arts. He also was into cage-fighting. He graduated from the University of Tennessee with an engineering degree.

INSIDE EDITION has obtained his resume and it shows that, intriguingly, he interned for the Tennessee Valley Authority - the federal corporation that runs dams and electrical power systems.

The Abdulazeez family are devout Muslims. In 2010, his sister, who wears a headscarf, complained to the local paper about being harassed over her religion.

In April, Abdulazeez was busted for a DUI. Gone was the clean-cut look – he grew a full beard. Just four days before the shooting, Abdulazeez wrote on his blog: "Life is short and bitter," and "don't let the society we live in deviate you from the task at hand."

A video posted on Facebook shows the final showdown between Abdulazeez and local police. Officers used a slow-moving cop car as a shield as they approach the killer. Abdulazeez was found dead.

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Two of the slain Marines were identified  Friday. One is Thomas Sullivan, a Purple Heart winner who survived two tours of duty in Iraq, only to be gunned down here at home.

And Skip Wells was 21 and had just completed boot camp.  He studied history at Georgia Southern Universtiy and joined the marines because of a "call to serve."

Now, security at military recruiting stations all across the nation have been beefed up in the wake of the Chattanooga shooting.

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