Boston bombing suspect Tamerlan Tsarnaev may have murdered his 'only American friend' in an unsolved triple killing two years ago, it emerged today.
Brendan Mess had his 'throat slit' alongside two other men in a Massachusetts apartment in 2011.
Former associates of the Chechan immigrant didn't initially suspect him of carrying out the gruesome attack, but thought it was strange he didn't attend his friend's funeral.
Now one man who knew Tamerlan through the gym where they trained said some of their social circle 'without even speaking about it beforehand have all been thinking' he could be involved.
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In the frame: Boston bombing suspect Tamerlan Tsarnaev (left) is now suspected by his former friends of murdering his 'only American friend Brendan Mess (right) in a brutal triple killing in 2011
The friend, who gave his name only as Ray, told BuzzFeed Politics: 'At the time, none of us would have thought it was Tam.
'It was just so emotional and we thought we had someone else who had done it.'
But since Tamerlan was identified as the suspect in the Boston Marathon bombings that killed three and injured 180, Ray believes his sudden disappearance after Mess's death may be a clue.
'Tam wasn't there at the memorial service, he wasn't at the funeral, he wasn't around at all,' Ray said.
'And he was really close with Brendan. That's why it's so weird.'
Ray said he met Tsarnaev in 2010 when they were part of a a social circle that centred on the Wai Kru Mixed Martial Arts gym in Allston where Tsarnaev trained as a boxer and had a shared interest in the Boston hip-hop group FlyRidaz.
He said they had a friendly, but not particularly close relationship and described Tsarnaev as a 'normal guy who wore regular American-ish clothes'.
But contact stopped when Mess and two other men - Raphael Teken and Erik Weissman - were murdered on September 12, 2011.
Dark past: Tamerlan, pictured in the gym in 2009, was arrested that year on suspicion of assaulting his girlfriend (not pictured)
Tamerlan was an avid boxer and spent a lot of time training for competitions, according to Johannes Hirn, who posted a photo essay entitled 'Will Box for Passport'
Their bodies were found covered in marijuana in an apartment in Waltham, Massachusetts, and had their throats slit with a knife or ice pick and around $5,000 was left at the scene.
Initially police said two other people had been there on the day and they were looking to question them, although no one has ever been charged.
Ray said there had been no forced entry, so police believe the killer was known the victim and was let into the apartment.
A year earlier, Tamerlan claimed to have just one American friend despite spending much of his life in the U.S.
The 26-year-old, who appears to have become increasingly radicalised over the last few years, was killed in a shoot-out with police on Thursday night.
His younger brother and accomplice, Dzhokhar, escaped during the running gun battle in the Boston suburb of Watertown, but was captured hours later after hiding in a boat in a backyard.
Wai Kru Mixed Martial Arts center owner John Allan said Tsarnaev and Mess used to work out at his gym together but Tsarnaev stopped coming after Mess was murdered.
Read more: http://www.dailymail.co.uk/news/article-2312814/Tamerlan-Tsarnaev-Friends-suspect-Boston-bomber-murdering-American-friend-2011.html#ixzz2RCYLZseG
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