Bosnian Serb general Ratko Mladic taunted Srebrenica survivors yesterday at the start of his trial for genocide, running his hand across his throat in an aggressive gesture of defiance.

Mladic, now 70, gave a thumbs-up and clapped his hands as he entered the courtroom in The Hague, where he faces possible life imprisonment for allegedly leading the slaughter of 8000 unarmed Muslim boys and men in Srebrenica in 1995, the worst massacre in Europe since the Second World War

In the packed public seating area, the mother of one of the Srebrenica victims whispered "vulture" several times as prosecutors opened their case.

Later, Mladic made eye contact with a Muslim woman in the audience and ran his hand across his throat, a gesture that led presiding judge Alphons Orie to hold a brief recess and order an end to "inappropriate interactions".

Wearing a dark suit and tie, Mladic sat with his spectacles in his hand, listening intently and jotting down notes as prosecutors made their opening remarks.

Prosecutor Dermot Groome said Mladic and other Bosnian Serbs had divided the territory of the former Yugoslavia along ethnic lines and implemented a common plan to exterminate non-Serbs.

"The prosecution will present evidence that will show beyond reasonable doubt the hand of Mr Mladic in each of these crimes," Mr Groome said.

Two dozen mothers of victims of the Srebrenica massacre gathered outside the court. Kada Hotic, who lost her 29-year-old son, husband and two brothers, said she was worried Mladic might not live long enough for the verdict, like the late Yugoslav president, Slobodan Milosevic, who died during his trial.

Mladic is the last of the main protagonists in the Balkan wars of the 1990s to go on trial in The Hague at the International Criminal Tribunal for the former Yugoslavia.

He is accused of orchestrating not only the week-long massacre in Srebrenica, at the time a UN "safe haven", but also the 43-month siege of the Bosnian capital Sarajevo, in which more than 10,000 people were killed.

The charges stemming from his actions as the Serb military commander in the Bosnian war of 1992-95 range from genocide to murder, acts of terror and other crimes against humanity.

But Mladic, who was arrested last May after 16 years on the run, has dismissed the charges as "monstrous" and says he is too ill to stand trial. The court entered a "not guilty" plea on his behalf.

The case has stirred up deep emotions in the Balkans and yesterday's trial was broadcast live on big screens in Sarajevo.

"I hope that many of those who believe Mladic is a Serb hero will change their minds, and that the trial will demonstrate he was just a criminal and a coward," said Fikret Grabovica, president of the association of parents and children killed in the siege of Sarajevo.

Mladic has been angry and defiant during pre-trial hearings, heckling the judge, shouting and interrupting the proceedings.

"The whole world knows who I am," he told a hearing last year. "I am General Ratko Mladic. I defended my people, my country - now I am defending myself."

Mladic was in charge of the Bosnian Serb army when, over several days in July 1995, Serb fighters overran the Srebrenica enclave in eastern Bosnia, theoretically under the protection of Dutch UN peacekeepers. Video footage at the time showed Mladic mingling with Muslim prisoners. Shortly afterwards, the men and boys were separated from the women, stripped of identification, and shot.

The dead were bulldozed into mass graves, then later dug up with excavators and hauled away in trucks to be better hidden in dozens of remote mass graves.

l Former Liberian President Charles Taylor said witnesses had been threatened and paid to testify against him in a trial that found him guilty of crimes against humanity.

Taylor, the first head of state to be found guilty by an international tribunal since the Nazi trials at Nuremberg, told the court in The Hague that the US had used the case to achieve regime change, not justice.