Vandals destroyed a monument to victims of a World War Two pogrom against Jews in Poland, covering it with racist inscriptions and swastikas in green paint, police said on Thursday.
It was the latest in a recent series of racist and xenophobic acts of vandalism targeting the small Jewish and Muslim communities in eastern Poland as well as the tiny Lithuanian minority.
At least 340 Jews were burned alive by their Polish neighbours in a barn in the 1941 pogrom in the eastern town of Jedwabne. The site was later turned into a memorial.
"On Wednesday a police patrol ran into the devastated site. We immediately started an investigation," said Andrzej Baranowski, police spokesman in the nearby city of Bialystok.
Vandals also smeared a wall surrounding the memorial with signs saying "I'm not sorry for Jedwabne" and "They were highly flammable". They obscured the Hebrew and Polish signs on the memorial itself with paint.
"This is a perfect example of vandalism and stupidity, but we don't know the exact motives yet," Baranowski added.
All the recent anti-Semitic and xenophobic incidents were probably perpetrated by the same people, Poland's interior ministry said this week, and they are all under investigation by the Bialystok police.
A 2001 Polish investigation concluded that the Jedwabne pogrom was inspired by Poland's then-Nazi occupiers and the case remains a traumatic memory for Jews and many Poles today.
Poland was home to Europe's largest Jewish population of some 2.5 million until World War Two, when most of its Jewish citizens perished in the Nazi-sponsored Holocaust.
The few who survived the war faced periodic oppression by the communist regimeinstalled in Poland after 1945.
Poland is a largely homogenous Roman Catholic country but religious and ethnic minorities are more common in eastern regions near the borders with Belarus and Ukraine.
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