The Polish embassy in Moscow had cleaners remove red paint from its walls on Wednesday, following a suspected retaliatory action for an incident that happened in Warsaw two days prior.
The perpetrator behind the latest incident has yet to be apprehended.
On Monday, the Russian ambassador to Poland was doused in red paint, as he visited the Soviet Military Cemetery in Warsaw.
That incident sparked a furious reaction from Moscow, which demanded a formal apology, and summoned Poland's ambassador to Russia, to lodge a protest.
However, Poland's Foreign Minister said the Russian envoy had been warned by Polish authorities that visiting the cemetery risked provoking an angry reaction, but he went along regardless.