Russia’s Federal Security Service (FSB) said on Saturday that it had been warned by the United States through established partner channels about preparations for a possible “terrorist attack” in Moscow and was taking appropriate security measures, Reuters reported citing Russian state news agency RIA reported.Separately, the US Embassy in Moscow confirmed it was aware of a “credible threat of a mass casualty event” at the Tsaritysyno Museum Reserve in the Russian capital.“The US Embassy in Moscow is aware of a credible threat of a mass casualty event TODAY October 31, at the Tsaritsyno Museum Reserve in Moscow at Dolskaya Ulitsa 1, Moscow, Russia 11569. The US government is coordinating with appropriate Russian authorities on a response,” it said in a statement.