Protesters in Poland doused Russian Ambassador Sergei Andreyev with red paint as he attempted to lay flowers at a Soviet military memorial cemetery in Warsaw for Red Army soldiers who died during World War II.
Video of the attack Monday showed red paint being thrown from behind Andreyev before another activist standing beside him throws some on his face as they protested Russia's unprovoked invasion of Ukraine.
Andreyev was surrounded by the protesters, who were holding Ukrainian national flags and chanting, "Fascist! Fascist!"
He and his delegation were prevented from placing flowers at the cemetery to mark the defeat of Nazi Germany in 1945.
Poland has been one of the harshest critics of Russia's war in Ukraine.
More than 3.2 million refugees have flooded into Poland from Ukraine as a result of the fighting, which began on February 24.