The family lived in Massachusetts before Zubeidat Tsarnaev jumped bail after her arrest on shoplifting and property damage charges in 2012. The parents moved the same year to Dagestan.
The Tsarnaevs are originally from the embattled Russian republic of Chechnya but fled from the brutal wars there in the 1990s. The two brothers were born in Kyrgyzstan and moved at different times to the United States.
Zubeidat Tsarnaev and her older son were both added by U.S. authorities to the Terrorist Identities Datamart Environment, or TIDE, database in 2011 -- a collection of more than a half million names maintained by the National Counterterrorism Center, an intelligence official said.
Russian authorities had raised concerns to U.S. authorities about her and her son, sources told CNN. But a U.S. official said that the Russian's case at the time was "thin."
Zubeidat Tsarnaev said the FBI had visited her family "several times" in 2011 with questions about her older son's "Islamic interests."
Putin: 'We were right'
Russian President Vladimir Putin on Thursday urged closer cooperation between other countries' security services in the wake of the Boston attack.
"If we combine our efforts, we will not suffer blows like that," he said during a live televised call-in session in Moscow on Thursday.
In his first on-camera comments since the bombing, Putin also lashed out against those in the West who have slammed Russia for human rights abuses in its actions toward Chechnya.
"Russia is among the first victims, and I hate it when our Western partners call our terrorists -- who committed some heinous crimes in Russia -- when they call them freedom fighters and never call them terrorists. They supported them," said Putin, accusing unnamed people or groups of providing Russia's foes with political, financial and "media" support.
U.S. authorities have come under fire at home, with lawmakers asking if the FBI and CIA failed to share information. Sources told CNN that Russia had separately asked the FBI and the CIA to look into Tamerlan Tsarnaev in 2011.
Sources: Suspect was unarmed in boat
More details, meanwhile, continue to emerge about the April 15 bombings as well as authorities' engagement days later with the two suspects.
A law enforcement official told CNN Thursday that at least one of the two bombs, the second to explode, was detonated by remote control.
The twin blasts killed three people and injured more than 260 others, 14 of whom had limbs amputated. As of Thursday evening, 34 of those wounded were still being treated at Boston hospitals, including one patient in critical condition.
The manhunt for those responsible ended last Friday, when Dzhokhar Tsarnaev was captured following a tense standoff after he'd hidden in a boat in the yard of a home in the Boston suburb of Watertown, Massachusetts.
The teenager was unarmed when he was wounded in a barrage of gunfire, and there was no firearm found in the boat, said several sources from difference agencies familiar with the investigation.