Hardcore Serbian nationalists are threatening to prevent the extradition of alleged mass murderer Radovan Karadzic by force.

Hard-line supporters of Serbian mass killer Radovan Karadzic are threatening to bring violent chaos to Belgrade on Tuesday with a huge rally in his support.

The former president will probably still be in the country after plans to extradite him to the UN war crimes tribunal on genocide charges hit delays on Monday.

There were fears that the ultra-nationalists plan to prevent Karadzic’s extradition by force. The rally organisers - the right-wing Serbian Radical Party - were bringing in supporters from all over Serbia and Bosnia.