US Embassy Warns of Credible Mass Casualty Threat at Moscow Museum as Site Closes and FSB Acts on US Tip

The US Embassy in Moscow said on Saturday that it is aware of a credible threat of a mass casualty event at the Tsaritsyno Museum Reserve in Moscow. The alert named the site at Dolskaya Ulitsa 1, Moscow, Russia 11569, and said the threat applied to today, October 31, 2026. The embassy said the US government is coordinating with appropriate Russian authorities on a response.

No attack has been reported. No confirmed reports of an incident at the site or of detentions had emerged at the time of reporting, and the warning concerns a threat, not an attack that has taken place. The museum reserve told the Telegram channel Mash that it had no information about a threat.

FSB says the warning came from the United States

Russia's Federal Security Service, the FSB, said it had received information from the United States through established partner channels about preparations for a terrorist attack in Moscow. The FSB said it was taking appropriate measures. RIA Novosti reported the FSB as saying that relevant work is being carried out.

The FSB statement, as reported, did not mention Tsaritsyno by name and did not describe what the information contains. The detail that links the American warning to the museum site comes from the embassy alert itself, which named the Tsaritsyno Museum Reserve and its street address.

Reuters reported, citing the RIA news agency, that the Tsaritsyno Museum Reserve has been temporarily closed and that access to the park is currently restricted. RIA cited Russian law enforcement agencies for the closure report.

What the embassy told people to do

The embassy told people to avoid the Tsaritsyno Museum Reserve location today, October 31, 2026. It told people to avoid the area, stay alert and avoid crowds. It also told people to be aware of their surroundings and to review their personal security plan.

The advice also covered practical steps. People were told to keep their cellphone charged, to carry proper identification and to monitor local media. The embassy also told people to enroll in the Smart Traveler Enrollment Program, known as STEP.

The site at the centre of the alert

The Tsaritsyno Museum Reserve is a palace museum and park complex south of Moscow. The site was founded in 1775 as a summer home for Russia's Catherine II. It is now a popular tourist attraction in Moscow, which is why a warning naming it for a single day drew quick attention.

Why the March 2024 warning is being recalled

The warning follows a pattern that Moscow has seen before. In March 2024, the US Embassy warned that extremists had imminent plans for an attack in Moscow. Days later, gunmen attacked the Crocus City Hall concert venue outside Moscow, killing more than 140 people.

That history is part of why a short embassy alert carries weight. In this case, the FSB has publicly said the information came from the American side and that work is under way in response.

For now, the confirmed picture is narrow. An embassy has named a place and a day and called the threat credible. The FSB has confirmed that it received American information about preparations for an attack in Moscow. The site is reported closed. Nothing in the confirmed reports says that an attack happened on Saturday.