French officials were holding a meeting on Monday to look at specific measures to step up security, such as checking bags on entrance to concert halls or places of worship.
When we look at the attack on Russia and Israel, the similarities are clear when it comes to the methods of the terrorists and the victims
The Federation of Jewish Organizations and Communities of Russia on Saturday night posted on Facebook a mourning candle with the date of the Moscow attack.
Haqiqatjou argues that in this terror attack on Russia, “it is likely that Israel's partner the CIA was involved. The US and Israel have a shared interest in destroying Russia."
Putin vowed to punish those behind concert massacre.
Ukrainian presidential adviser Mykhailo Podolyak said on Friday that Kyiv had nothing to do with Friday's attack by gunmen at a Moscow concert hall.
The United States had warned Russia on March 8 that "extremists" had imminent plans for an attack in Moscow.
The student is currently serving a 10 day sentence.
The embassy, which has repeatedly urged all US citizens to leave Russia immediately, gave no further details about the nature of the threat.
Russia's FSB said that the members of the organization had been planning "to commit a terrorist act against one of the Jewish religious institutions in Moscow."