An ultimate fighter who once sparred with Tamerlan Tsarnaev, one of the suspected Boston Marathon bombers who died in a shootout with police, told MyFoxBoston that he dismantled the former boxer in the ring and could have ‘finished him’ with his bare hands.

John "Doomsday" Howard said in an interview that Tsarnaev was a good boxer who was known to be cocky and would beat up guys at various gyms. Tsarnaev requested a sparring match with a UFC fighter and Howard took him up on the offer.

"By the fourth time we sparred, he kinda got a little cocky and tried to pick me apart; really tried to hurt me," Howard said. "Once I got the OK to go hard I gave him my famous left hook and broke his nose. When his hands went up, I came with a right hook and dropped him with a body shot. He got humbled that day."

Howard said that after the bombings he couldn't believe Tsarnaev was involved.

"I felt betrayed. I'm from Boston. I love my Boston people. To see my Boston people hurt and to see this man do this – and I had some interaction with him – it was unbelievable," said Howard. "I felt like if I knew something or had some clue I could have handled it. I could have probably finished him myself with my bare hands. You know, put him down for good."

Howard continued, "Terrorists don't say ‘I'm a terrorist.' They come with open hands and stab you in the back the first chance they get."

Dzhokhar Tsarnaev, Tamerlan’s brother and suspected cohort in the marathon bombings, meanwhile pleaded not guilty last month to 30 charges leveled against him in connection with the deadly April 15 attack.