Washington: Russia intercepted a communication between the mother of the accused Boston Marathon bombers and someone who may have been one of her sons "discussing jihad" in 2011, a US official said.
The Tsarnaev brothers — Tamerlan and Dzhokhar — are accused of planting homemade bombs that exploded at the finish line of the Boston Marathon April 15, killing three people and injuring 180.
Tamerlan, 26, was killed during a shootout with police in the Boston suburb of Watertown. Dzhokhar, 19, was apprehended after eluding a massive manhunt that saw the city of Boston and many of its suburbs shut down.
According to CNN, the US official described the conversation as vague.
Russians handed over the intercept to the FBI in the last few days, the official said.
The family lived in Massachusetts before Tsarnaev's mother Zubeidat Tsarnaeva jumped bail following her arrest on charges of shoplifting in 2012. The parents moved back to Dagestan, a semi-autonomous republic in southern Russia that year.
Zubeidat Tsarnaev has denied the reality of the bombing. She believes it was fake. She said she has seen a video pushing the idea, and that there was no blood, that paint was used instead.
CNN said the FBI was conducting an investigation over an interview with Tamerlan Tsarnaev after Russia expressed concerns in 2011.
The FBI said at the time it found nothing to justify pursuing the matter further, and that Russia did not respond to US requests for additional information.
Russia also raised questions about, Zubeidat Tsarnaeva, when Moscow approached the US about concerns regarding Tamerlan Tsarnaev, according to several sources.
The mother's name was subsequently added to the Terrorist Identities Datamart Environment (TIDE) database at the same time as her son's, an intelligence official told CNN.
TIDE is a collection of more than half million names of suspected terrorists. It is maintained by the National Counterterrorism Center.
The FBI did interview the mother in 2011 as part of the investigation into her son. The case was closed after several months.
The mother said on Friday that she and her husband had left their home in Dagestan for another part of Russia.
The father, Anzor Tsarnaev, earlier said he had planned to travel to the US. But that the trip has been delayed indefinitely for health reasons.
The mother will not be flying to the US, where she is wanted on charges of shoplifting and destruction of property.