According to a federal report, Russia refused to give the U.S. vital information on the men responsible for the Boston Marathon bombings last year, CBS News reported.
Though the Federal Bureau of Investigation (FBI) knew of Tamerlan Tsarnaev since 2011 -- two years prior to the bombings -- Russian authorities never disclosed he had discussed jihad with his family.
Bob Orr, justice and national security correspondent at CBS News, reported last year that Russian officials secretly recorded a phone conversation between Tsarnaev and his mother where they discussed radical theories. However, they did not tell U.S. authorities about the call until after April 2013.
Another conversation between Tsarnaev's mother and another person currently under investigation by the FBI in a separate case was also recorded, according to the AP.
Had the U.S. listened to the phone conversations, they could have been able to prevent the tragedy at last year's Boston Marathon by watching Tsarnaev and his younger brother, Dzhokhar, more closely, the report claims.
In June 2011, the FBI closed a case looking into Tamerlan and his mother due to a lack of sufficient information.
"That certainly would have added texture to the suspicion and concerns that the FBI would have had," said Juan Zarate, national security analyst at CBS News.
While Zarate did not say he believed the additional information could have definitely prevented the attack, he still suggests it could have had a significant impact on the FBI's investigation.
"The FBI did talk to the elder brother. They did investigate him. They certainly did their due diligence in terms of the information they had.
"Whether or not this would have allowed them further evidence to allow for deeper surveillance, for example, wiretap or to allow them to investigate for a longer period of time, which would have given them insights into his travel or into his plotting, that's uncertain. But I think this certainly would have added texture to what the FBI knew, and certainly, you've heard the FBI worried about the fact that they did not get this information from the Russians."
