"The U.S. 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 U.S. government is coordinating with appropriate Russian authorities on a response," the statement said.

The statement also warned people to avoid the area and take measures to ensure personal safety. 

Later on Saturday, state media reported that the Federal Security Service (FSB) had received information from the U.S. regarding the potential terrorist attack. 

"We have received information from U.S. partners regarding plans for a terrorist attack in Moscow. We are taking appropriate action," the FSB told state media.

Tsaritsyno was evacuated Saturday while musician Lilia Pechenkina was playing a concert. "Just as I was playing the last piece in the program, an evacuation announcement came over the loudspeaker," Pechenkina told news outlet Ostorozhno, Novosti!.

The Tsaritsyno Museum Reserve has been closed for "technical reasons," a journalist from Ostorozhno, Novosti! was told by security.

Around 50 law enforcement officers have been dispatched to the area, and police vehicles are patrolling the perimeter, the Baza Telegram channel, which allegedly has ties to the Russian security services, reported.

In 2024, the U.S. warned Moscow of an impending terrorist threat ahead of the March 22 Crocus City Hall attack, which left 145 people dead and hundreds more wounded.

At the time, Russian spy chief Sergei Naryshkin called the information "too general."

"The Federal Security Service [FSB] received some information from the U.S. intelligence services that such a thing was unfortunately possible. But as our Russian colleagues said, the information was too general and did not allow us to fully identify those who committed this terrible crime," he said.