The elder Boston bomb suspect, who died last night in a shootout with police, was apparently interviewed by the FBI two years ago following an international tipoff.
According to a US law enforcement source, an unidentified foreign government requested the agency speak to Tamerlan Tsarnaev.
The source, who remained anonymous, said no "derogatory" information was found against the Chechen and the matter - the nature of which is still not known - was put "to bed" by officials.
US authorities said the official's claim is the first indication that Tamerlan Tsarnaev and his younger brother, Dzhokhar, were known to security officials prior to Monday's bombings.
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.