The U.S. Embassy in Russia issued a warning on March 7 that "extremists have imminent plans to target large gatherings in Moscow" and urged American citizens to stay away from concentrations of people over the next 48 hours.
The embassy did not specify what kind of threats they referred to, or who might be behind them. The U.K. Embassy in Russia also repeated the advisory issued by the U.S.
Russia's Federal Security Service (FSB) said on March 7 that its agents had thwarted a potential Islamic State terrorist attack on a Moscow synagogue. The Russian state-owned TASS news agency said that FSB agents had killed several militants who were planning the attack, citing the FSB's press office.
It is unclear if the incident is related to the U.S.'s warning.
The U.S. currently has a "level 4" travel warning for American citizens who are considering going to Russia, the highest level of such advisories.
The warning, which says "do not travel," adds that there can be unpredictable consequences due to Russia's full-scale invasion of Ukraine and limited ability of the U.S. Embassy to assist American citizens.
There is also a heightened "potential for harassment and the singling out of U.S. citizens for detention by Russian government security officials."
U.S. citizens traveling or living in Russia "should depart immediately," the embassy said.
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