Tamerlan Tsarnaev reportedly had a telephone conversation with his mother vaguely discussing jihad. (Wikimedia Commons)

The conversations are significant because they might have provided enough evidence for the FBI to conduct a more thorough investigation of the  Tsarnaev family had they been revealed earlier. Instead, Russian authorities told the FBI only that they had concerns that the older brother Tamerlan and his mother were religious extremists. The FBI conducted a limited investigation and closed the case in June 2011.

Tamerlan and his younger brother, Dzhokhar, are suspected of detonating two bombs near the finish line of the Boston Marathon, killing three and injuring more than 260. Tamerlan was killed in a gunfight with police and Dzhokhar is under arrest.

More from the AP:

In the past week, Russian authorities turned over to the United States information it had on Tamerlan and his mother, Zubeidat Tsarnaeva. The Tsarnaevs are ethnic Chechens who emigrated from southern Russia to the Boston area over the past 11 years.

Even had the FBI received the information from the Russian wiretaps earlier, it's not clear that the government could have prevented the attack.

In early 2011, the Russian FSB internal security service intercepted a conversation between Tamerlan and his mother vaguely discussing jihad, according to U.S. officials who spoke on condition of anonymity because they were not authorized to discuss the investigation with reporters.

The two discussed the possibility of Tamerlan going to Palestine, but he told his mother he didn't speak the language there, according to the officials, who reviewed the information Russia shared with the U.S.

Zebeidat Tsarnaeva has denied that she or her sons are involved in terrorism, claiming that her sons have been framed by  the U.S.

Authorities have not found a connection between the brothers and a foreign terrorist group.

Read the full story at the Associated Press. Find more Neon Tommy coverage of the Boston Marathon bombings here.

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