Alarm as US embassy in Moscow issues rare 'mass casualties' notice: 'You don't see this'

The U.S. Embassy in Moscow warned Saturday of a “credible threat” of an attack that could cause mass casualties at a popular park in the Russian capital. Observers noted the warning was strikingly specific.

“The U.S. Embassy in Moscow has learned of a credible threat of an incident that could result in mass casualties TODAY, October 31, on the grounds of the Tsaritsyno Museum-Reserve in Moscow,” the embassy wrote on X. It said the U.S. government “is coordinating response measures with the relevant authorities of the Russian Federation.”

The embassy told Americans to avoid the park Saturday, stay away from large crowds, keep their phones charged and carry identification. Tsaritsyno is a sprawling former royal estate in southern Moscow that draws large crowds.

The alert quickly drew comparisons to the March 2024 Crocus City Hall attack outside Moscow. In that attack, gunmen linked to the Islamic State killed more than 140 people at a concert venue, weeks after the U.S. Embassy publicly warned that extremists were planning to target large gatherings in Moscow.

“Last time I remember this kind of specific alert it was before the Crocus City concert hall ISIS-linked attack in 2024,” wrote ABC News international correspondent Patrick Reevell, calling the warning “unusual.”

Sarah Adams, a former CIA targeting officer and author of “Benghazi: Know Thy Enemy,” shared the alert with a brief comment: “You don’t see this everyday.”

Kirill Dmitriev, the head of Russia’s sovereign wealth fund and a Kremlin envoy who has taken part in talks with the Trump administration, cast the warning as a sign of improving relations.

“In a spirit of goodwill, the US has informed Russian security services and issued a public alert about a possible terrorist attack in Tsaritsyno Park in Moscow,” Dmitriev wrote. “US-Russia security services cooperation is vital for global security.”

The embassy did not say who was behind the threat or what kind of attack it anticipated. There were no reports of an attack as of publication.