A Chechen leader said the Tsarnaev brothers' "root of evil" is in the United States, not in Chechnya.
"The root of evil should be looked for in the United States," said Ramzan Kadyrov, the Head of the Chechen Republic.
"(The brothers) grew up and studied in the United States and their attitudes and beliefs were formed there. Any attempt to make a connection between Chechnya and the Tsarnaevs is in vain," he added in a post in the Instagram website.
Detectives in Boston are looking further afield as they piece together their case against Marathon suspect Dzohkhar Tsarnaev.
The uncle of Boston bombing suspect Tamerlan Tsarnaev described his recent visit to Dagestan in Russia and his great shock at the attacks.
Both men were enrolled in a school in Dagestan, a neighbouring region that was drawn into Chechnya's violence during the 1990s.