ZAGREB (AFP-EJP)---The Orthodox Serbian Church of Croatia said it has received a written message threatening the country’s Serbs and Jews with “extermination”.

The message was signed by supporters of Hajduk Split, one of the most famous and successful Croatian football clubs.

"We received in the premises of our Church in Split (south) a letter with a neo-Nazi content threatening in a brutal manner the Serbian and Jewish in Croatia,” the Orthodox Church, which published the letter on its website, said a in press release.

"Ask yourself if these are your last days. We are going to exterminate you all,” the letter read. It also contains slogans used during WWII like "Let us hang the Serbians very high" and "Jewry outside.” .

The Church informed police and an inquiry is under way to identify the authors of the threat.

The letter is signed "Hajduk Jugend", the name that neo-Nazi supporters of Hajduk give themselves in a direct reference to 'Hitler Jugend' (Hitlerian Youth).

These supporters showed up for the first time publicly in November 2007 by walking in the coastal city of Split dressed in black T-shirts featuring the words "Hajduk Jugend” and an eagle atop Hajduk’s logo  resembling a Nazi Party symbol.

These T-shirts were even on sale on the official internet site of Torcida, the official group of Hajduk supporters.

Hundreds of thousands of Serbians, Jews, gypsies and anti-fascist Croats died in concentration camps set up by the Croatian pro-Nazi regime during WWII.