Mohammad Youssuf Abdulazeez shot and killed four U.S. Marines and wounded three others at two separate military sites in Chattanooga, Tenn., Thursday. He was subsequently killed by police in an exchange of gunfire.

Who Was Mohammad Youssuf Abdulazeez?

Abdulazeez, 24, grew up in the Hixson neighborhood of Chattanooga and went to Red Bank High School, playing for the school’s wrestling team. He graduated from the University of Tennessee at Chattanooga in 2012 with a degree in engineering. In the two years since getting his college degree, Abdulazeez is said to have worked at cellphone kiosks in local malls, and briefly lived in the Middle East before returning to his hometown.

People who grew up with Abdulazeez or trained with him in mixed martial arts could not believe that the young man they knew was the shooter on Thursday.

“There were tears in my eyes,” Abdulazeez’s former mixed martial arts coach Scott Schraeder told CNN. “He was one of the nicest kids we trained.”

Schraeder said that Abdulazeez was a devout Muslim, who would often take a break from training at 6 p.m. to say his prayers. However, Schraeder never considered that Abdulazeez could be an extremist or thought that he was “overly religious” in anyway.

“His favorite training partner to grapple with — not striking, but actually submission grapple with, when you’re actually on the ground in close proximity contact with — was a Russian Jew,” Schraeder recalled. “Hardly what you would see as someone who would be a radical Islamist.”

Another fighting coach of Abdulazeez, Almir Dizdarevic, was also in disbelief about the story that broke about his former trainee on Thursday. Dizdarevic, who would often bump into Abdulazeez at local mosques, does not believe that he could have been radicalized by anyone in Chattanooga.

On Thursday, Abdulazeez, armed with an AK-47 style rifle, opened fire at a military recruiting center in a strip mall before driving seven miles to a U.S. Navy operational support center, where he shot dead four marines. It is believed that Abdulazeez, who was killed at the scene, had acted alone.

Prior to the shooting, Abdulazeez had not been in any U.S. databases of suspected terrorists, according to The Washington Post.

“We will treat this as a terrorism investigation until it can be determined that it is not,” said FBI special agent Edward Reinhold.

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