`They were led away and they were all killed'

The buses and lorries the Serbs had arranged to remove their victims from Srebrenica stretched for half a mile outside the Dutch UN base camp in Potocari, a village between Srebrenica and the Serb-held town of Bratunac. From a distance, the Dutch soldiers said the convoy looked like a train with men in uniform forcing people on board carrying their meagre possessions. The scene had a horrible familiarity.

"It was like Schindler's List," one of the Dutch soldiers later recalled. "The Muslims told us they would be murdered. One of them gave me money, German marks, and a gold chain. I handed them back because there was nothing that I could do for him. He then walked over to one of the Serb soldiers, who accepted them, but then spat in his face and began beating him with a rifle butt. At that moment, I remember thinking: `Man, now you have lost everything.' He was taken to the football stadium in Bratunac along with the other men and there - although I am not supposed to know it, but everybody does - they were all killed."

The Dutch soldier and 350 comrades were there to protect the inhabitants of the UN-designated "safe area". But when the Bosnian Serbs launched their offensive against the town on the morning of 6 July, the Dutch defence collapsed. It led to one of the worst acts of genocide since the Second World War.

The Serb capture of Srebrenica 10 weeks ago was a fateful turning point in Bosnia's long, miserable war. Militarily, it set in motion the chain of events that led to the recent Nato air raids against the Serbs, the Croatian military victory in Krajina and the Muslim advance through central Bosnia in recent days.

Yet Srebrenica also marked perhaps the West's deepest deep humiliation in Bosnia. Dutch soldiers watched helplessly as men were marched before their eyes in their hundreds to the slaughter. Yet the shame of Srebrenica is more than that. Many of the Muslims in the town surrendered to the Dutch, seeking the UN's protection, only to be handed over to the advancing Serbs. Many of these people were then killed.

The Dutch troops were so widely despised by the Muslims that when they retreated from their forward observation posts they were shot at. One was killed. Dutch soldiers admit that relations with the Muslims had deteriorated so far that when the advancing Serbs arrived, the UN forces were no longer sure "who the good guys and the bad guys were".

The Dutch, sent to protect the Muslims, now stand accused of complicity in the mass killings that followed the Serb victory.

Private Guido den Hertog stopped in the middle of his story and stared off into space, fidgeting absent-mindedly with the coasters on the bar in the sleepy town of Arnhem. Dutch soldiers who witnessed the fall of Srebrenica often break off in mid-sentence when recounting their experiences. A thought gets snagged on a memory and their eyes glaze over as they replay it. Sometimes the pause lasts for the briefest moment. With Den Hertog, it is painfully long.

Den Hertog, a medic with the Royal Dutch Army's 13th Air Mobile Infantry Battalion was recalling how his unit got out of Srebrenica on 11 July, when the town fell. Bosnian Serb guns were raining shells on the centre, forcing thousands of the Muslims to the gates of the small Dutch compound on the outskirts of town begging for protection. The Dutch said they could only shelter the sick and wounded. A mortar bomb landed in the crowd. The panic, Den Hertog said, was "biblical". The soldiers got the newly wounded into the trucks and a convoy of armoured vehicles and lorries ploughed through the crowd north toward the battalion headquarters in Potocari.

Hundreds of desperate people jumped on to the retreating convoy, clinging to bumpers, battery cases, anything. During the exodus several people lost their grip and fell under the wheels of the vehicles. It was here that Den Hertog stopped.

When he came round, he explained: "Seeing those bodies, the injured; trying to keep people off the truck; hearing those explosions, all the shooting; it was real war. We never expected to be in the middle of that."

Many of the Dutch viewed a tour in Srebrenica as chance to do something positive. Others saw it as a chance to get double pay with nothing to spend it on. But anyone who knew Srebrenica could have told them what might lie in store.

Srebrenica was declared a "safe area" by the UN Security Council on 16 April 1993, after a bloody Bosnian Serb drive to take the town. The Serb onslaught had followed a Bosnian Muslim counter-offensive against a vicious Serb "ethnic cleansing" campaign, which had killed and driven out thousands of non-Serbs from the Drina valley.

Srebrenica's Muslims did not draft the dirty rules by which the war in Bosnia was fought, but they adapted to them well. In December 1992, I sat on a hill in Serbia and watched Bosnian troops from Srebrenica burn Serbs out of their homes in a nearby village. The Muslims' successes, and their excesses, fed the Serb desire for revenge, but the UN persuaded the Serbs to halt their drive against the town in exchange for disarming it. The result was a besieged enclave, measuring roughly 9 miles by 10 miles, whose peacetime population of 18,000 was swollen to 42,000 by the influx of Muslim refugees.

The Serbs never lifted their siege. They ensured that the UN forces were run down. Dutch soldiers were allowed to leave on holiday, but they were not allowed to be replaced; the number of UN soldiers was reduced from 600 in January to around 350 in July. The battalion commander, Lieutenant Colonel Ton Karremans, warned UN peacekeeping headquarters and the Netherlands that he could no longer do his job. He asked for help, but it never came.

The inhabitants came to see the UN troops not as protectors, but as little more than jumped-up prison guards. "The Muslims were never straightforward. To your face they would say `hello' or hold out their hands, but behind your back they would point a gun at you or try to steal from you whenever they could," said Sergeant Johan Bos.

The antipathy between the soldiers and Srebrenica's inhabitants was so fierce that the troops came to see the Serbs as allies. The Dutch army's Chief of Staff, General Hans Couzy, told the daily NRC Handelsblatt, "To my surprise I discovered from the highest to the lowest a euphoric mood that the Serbs were the good guys."

One incident illustrates why the Dutch felt this way. During the Serb offensive, Bosnian soldiers threatened to kill Dutch troops if they abandoned their posts. On 8 July, they killed Private Raviv van Rensen as his unit retreated from an observation post that had fallen to the Serbs.

"After Raviv was killed, we asked ourselves: why are we here? Who are the good guys and who are the bad guys?" said Den Hertog, who treated the mortally wounded soldier.

On the front line, Pte Raviv's death put the Dutch in an acute dilemma. They were reluctant to take on the heavily armed Serb attackers. Yet they did not want to withdraw, for fear they would be killed by the Muslims.

"I found myself standing on a ridge with the Muslims behind me and the Serbs in front of me. Well, I wasn't going back. So we waited, and after a while the Serbs came and told us that if we surrendered we would be well treated and we would go home as soon as possible. So we gave up our arms and equipment and that was that, they took us away," Sgt Johan Bos says.

The Dutch debacle has shocked public opinion in the Netherlands. When the blue helmets returned, they were given a heroes' welcome. The euphoria has been replaced by shame.

Perhaps most damning were the accusations from Srebrenica's former inhabitants. One woman in Tuzla recently told a group of reporters: "We surrendered to the Dutch. This means they had an obligation to defend us. The UN soldiers kept saying, `No problem, no problem.' And yet the Serbs took away whomever they wanted in front of them. Meanwhile, the bastard of a commander was drinking brandy with the Serbs, with [the commander] General Mladic himself. The Serbs filmed him; he knew what he was doing."

The Dutch defence ministry at first denied the reports, but finally acknowledged that, yes, some atrocities had been committed in front of the soldiers; yes, many soldiers hated the Muslims, but only the combatants, not the people; yes, some soldiers did voluntarily surrender their position to the Serbs, but by that time the Serbs had already overrun them. And yes, Lt-Col Karremans had been videotaped drinking champagne, not brandy, with the Bosnian Serbs, but it was not a voluntary act.

After further investigation, the defence ministry was forced to admit that it accidentally destroyed what might have been crucial evidence of war crimes, a roll of film with pictures of 10 male victims of a summary execution. A videotape showing alleged atrocities had been erased. Finally a document emerged, signed by the Dutch officers, which seemed to countenance ethnic cleansing and absolved the Serbs of wrongdoing.

Some pundits said the Dutch suffered from the "Stockholm syndrome", in which people in hostage-like situations start to identify with their captors. Others blamed the UN system for creating and then failing adequately to provide for the "safe areas". Critics said the soldiers could have defended the enclave but refused. Parliament called for a military inquiry, which is due to report at the end of the month.

The effect on the liberal Dutch public has been profound. The nation that saw itself as the protector of Anne Frank and the inheritor of a great tradition of tolerance was confronted with the possibility that its sons and daughters had become accomplices to some of the most heinous war crimes in Europe since the Second World War.

Deciding what they should have done will not be easy, warns Den Hertog. "There is nothing we could have done. Still, I and many of the guys sometimes ask ourselves if there was something more we could have done. If, if, if - it's the biggest word in the world."