WASHINGTON — In March 2011 , the Russian security service sent Movement.Transportation.Unspecified a stark warning to the F . B . I . , reporting that Tamerlan Tsarnaev was “ a follower of radical Islam ” who had “ changed drastically since 2010 ” and was preparing to travel Movement.Transportation.Unspecified to Russia ’ s turbulent Caucasus to connect Contact.Contact.Meet with underground militant groups . Six months later , Russia sent the same warning to the C . I . A .

WASHINGTON — In March 2011 , the Russian security service sent Movement.Transportation.Unspecified a stark warning to the F . B . I . , reporting that Tamerlan Tsarnaev was “ a follower of radical Islam ” who had “ changed drastically since 2010 ” and was preparing to travel Movement.Transportation.Unspecified to Russia ’ s turbulent Caucasus to connect Contact.Contact.Unspecified with underground militant groups . Six months later , Russia sent Contact.Contact.Unspecified the same warning to the C . I . A .