Arkan -- whose real name was Zeljko Raznjatovic -- was the leader of the Serbian Unity party, but he also controlled one of the most infamous death squads which emerged during the break-up of Yugoslavia, Arkan's Tigers.

Many Moslems and Croats are believed to have died at the hands of the group both in Bosnia-Hercegovina and Croatia, and also it is reported in Kosovo -- although Arkan denied that.

A former BBC correspondent in Belgrade says Arkan's links with both organised crime and the Yugoslav intelligence services were well known. Our correspondent says he is believed to have acted as a hired killer for Yugoslav intelligence, and before the Yugoslav wars he was notorious as a gangster and bank robber.

Our correspondent adds that whoever killed Arkan removed a vital witness as to who in Belgrade gave the orders for some of the worst war crimes in recent European history.

From the newsroom of the BBC World Service