Demonstrators in Warsaw on Monday threw red paint at the Russian Ambassador, preventing him from placing flowers at a cemetery for Soviet soldiers in Poland.
According to news agency PAP, when the Russian ambassador Sergey Andrejev arrived at the Soviet Military Cemetery in Warsaw with his delegation, a number of Ukrainian and Polish protesters greeted him with shouts of “murderer’’ and “fascist’’.
A red liquid was then thrown at Mr Andrejev, the report said, causing the ambassador and his delegation to return to their car.
May 9 is a holiday in Russia marking the anniversary of the Soviet victory over Nazi Germany in World War II.
The Soviet cemetery in Warsaw was constructed years after the end of the war and the remains of more than 20,000 soldiers who died between 1944 and 1945 were buried there.
Poland has taken in more than 3.2 million refugees from Ukraine since the beginning of the Russian invasion on February 24.