The image of two individuals hung from a tree harkens back to the genocide committed by the Croatian Ustasha fascists against the Serbs in World War II.
Serbs were murdered, men, women and children, by the hundreds of thousands in concentration camps in Croatia, half of which were run by Catholic priests with the knowledge of the Vatican.
The horrific atrocities committed in Croatia death camps were some of the most grisly of the war.
Anti-Serb hate message in front of Zagreb kindergarten
A shocking sticker depicting people hanged on a tree, with an inscription reading, “Serbian family tree,” has been photographed in Croatia’s capital Zagreb.
Source: B92 Wednesday, May 25, 2016 | 09:56

The sticker was seen at the entrance to a kindergarten.
The photograph was posted on Twitter by Balkanist editor-in-chief Lily Lynch, an American who lives in Serbia.
“Serbs on willows” (“Srbe na vrbe”) is a slogan often used by extreme nationalists in Croatia.
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