Alexander Bortnikov, head of Russia s Federal Security Service (FSB). AP
Russia has asserted that Ukraine was involved in Friday's massacre, even after President Vladimir Putin acknowledged "radical Islamists" had carried it out.
"We believe the action was prepared both by the radical Islamists themselves and, of course, facilitated by Western special services, and Ukraine's special services themselves have a direct connection to this," FSB head Alexander Bortnikov was cited as saying by Russian news agencies.
He also asserted that the attackers tried fleeing over the Ukrainian border.
"I'll let you in on a little secret: they were going to be greeted as heroes on the other side," Bortnikov said.
He added that while Russia understood who organised the attack, "the one who ordered it has not been identified yet".
Islamic State jihadists have said several times since Friday that they were responsible, and IS-affiliated media channels have published graphic videos of the gunmen inside the venue.
*This story was edited by Ahram Online
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