ORLANDO (CBSNewYork/AP)The gunman who killed 49 people at a gay nightclub in Orlando had high praise for the Boston Marathon bombers.

Harold Shaw, special agent in charge of the FBI’s Boston division, said Monday that Omar Mateen referred to Dzhokhar and Tamerlan Tsarnaev as his “homeboys” during a 911 call he made early Sunday while he was gunning down people in the Pulse nightclub.

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Shaw and Massachusetts State Police said evidence collected so far shows no connection between Mateen and the Tsarnaev brothers.

The Tsarnaevs planted two bombs near the finish line of the marathon on April 15, 2013. The explosions killed three people and injured more than 260.

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Tamerlan Tsarnaev was killed during a getaway attempt several days later. Dzhokhar Tsarnaev was sentenced to death for his role in the bombings.

Mateen also pledged his allegiance to the Islamic State of Iraq and Syria on the 911 call.

ISIS has taken responsibility for the nightclub attack.

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