The US Embassy in Russia issued a warning that "extremists have plans to target large gatherings in Moscow" and urged American citizens to stay away from places where people gather for the next 48 hours.
The embassy does not specify what the threats are and who may be behind them. The UK embassy in Russia also reiterated the recommendation issued by the US, the Kyiv Independent reported.
On March 7, Russia's Federal Security Service (FSB) announced that its agents had prevented a potential Islamic State terrorist attack on a Moscow synagogue. Russia's state news agency TASS reported that FSB agents killed several militants who planned the attack.
It is not clear whether the incident is related to the US warning.
The US currently has a "level 4" travel warning for US citizens considering going to Russia, the highest level of such advice.
The warning, which reads "do not travel," added that there could be unforeseen consequences due to Russia's full-scale invasion of Ukraine and the limited ability of the US Embassy to provide assistance to American citizens.
There is also an increased "possibility of harassment and sequestration of American citizens for detention by Russian government security officials"./BGNES