Vandals have desecrated a memorial to to victims of a World War Two pogrom against Jews in Jedwabne, Poland, covering it with racist inscriptions and swastikas in green paint.
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.
"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.
At least 340 Jews were burnt 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.
After years of silence on the massacre, the publication in 2000 of the book "Neighbours" by American historian of Polish origin, Tomasz Gross, highlighted the involvement of local people in the crime and caused great psychological shock in Poland
In 2001, the Polish president at the time, Aleksander Kwasniewski, apologized for the massacre on the occasion of his 60th birthday.
Last July, the current president, Bronislaw Komorowski, again apologized in a message read during the ceremonies at the foot of the Memorial to victims of the massacre. He also met senior officials of the Jewish community in Poland, the Catholic Church and the government.
All the recent anti-Semitic and xenophobic incidents were probably perpetrated by the same people, Poland's interior ministry said this week.
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 Holocaust.