The US Embassy in Moscow warned on October 31 of a possible mass-casualty incident at the Tsaritsyno museum-reserve. The embassy described the threat as credible based on information available to it. The warning applied specifically to October 31 and identified the park's address as 1 Dolskaya Street.
The embassy advised people to stay away from Tsaritsyno, avoid crowds and monitor updates. It also said the United States was coordinating with Russian authorities.