Boxers call bombing suspect 'a beast'

Long before the world knew of his brutality, the boxing community here in Boston took note of Tamerlan Tsarnaev. He fought in bouts all over town and tournaments around the country, even competing in the 2009 Golden Gloves championships.

Tsarnaev told one interviewer he aspired to box on the U.S. Olympic team, but that dream stalled after his petition for citizenship was denied.

The Wai Kru mixed martial arts gymnasium in Allston, Massachusetts is where Tsarnaev used to work out. He was said to have not had a lot of respect for other trainers at other gyms because of their foul language. He worked out at Wai Kru often, and was regarded as one of best boxers.

Tsarnaev disappeared for sometime but then reappeared a few weeks ago, walking around acting as if he owned the place, and was asked to leave because he was being disrespectful to other people working out at the gym. A few days ago, law enforcement came and took the surveillance equipment from the gym as part of their investigation.

One fellow boxer told CNN Tsarnaev struck an intimidating figure in the gym, calling him a "premiere athlete," with a reputation as "a beast, an animal" in the ring.

Trainer Eddie Bishop traveled with him to a national competition, and said he thought Tsarnaev was eccentric from the moment he met him.

"He wore cowboy hats, leather pants, cowboy boots," said Bishop.

Bishop says Tsarnaev was talented but not tenacious

"He had a really big punch. He knocked a lot of people out. But, you know, he lacked that fighter's heart," said Bishop. "If he couldn't get you out of there, he quit."