The Bosnian town of Višegrad nestles in the valley of the Drina river at a particularly beautiful moment in its flow, where precipitous rocks part, giving way to a verdant valley. Spanning the river is a glorious bridge, iconic of Bosnia: an Ottoman structure of pumice stone, hewn in 1571 and the inspiration for a novel by Ivo Andrić, Bridge Over the Drina, which won its author the Nobel prize for literature. In the book, the bridge bears silent witness to Bosnia's history. Andrić died in 1975; but suddenly, seventeen years later, the bridge was bloodily defiled, turned into a slaughterhouse.

For centuries, although wars had crisscrossed the Drina, Višegrad had remained a town two-thirds Bosnian Muslim and one-third Bosnian Serb. The communities entwined, few caring who was what. But in the spring of 1992, a hurricane of violence was unleashed by Bosnian Serbs against their Muslim neighbours in Višegrad, with similar attacks along the Drina valley and other parts of Bosnia. Višegrad is one of hundreds of forgotten names, while the iconic Srebrenica echoes down history.

But Višegrad was especially vicious. Night after night, truckloads of Bosnian Muslim civilians were taken down to the bridge and riverbank by Bosnian Serb paramilitaries, unloaded, sometimes slashed with knives, sometimes shot, and thrown into the river, dead or in various states of half-death, turning the turquoise of the Drina red with blood. As well as the slaughter on the bridge, hundreds of Muslims were packed into houses across Višegrad and incinerated alive, including women and children. Višegrad was, too, the location for the one of the most infamous rape camps, at a spa called Vilina Vlas, where Muslim women and girls were violated all night, every night, to the point of madness and sometimes suicide.

Blood on his hands

As elsewhere, the pogrom was carried out on orders from the Bosnian Serb leader Radovan Karadžic and his military counterpart General Ratko Mladić, both still wanted for genocide. And as elsewhere, the persecution and mass murder was overseen by a ‘Crisis Committee’, established in every Bosnian Serb community. But anyone who survived the ravages of Višegrad will testify that the atrocities invariably bore the hallmark - directly or indirectly - of one man above all: Milan Lukić. On Monday, after seven years on the run from the war-crimes tribunal in The Hague, he was arrested outside his apartment in Buenos Aires.

For many in Bosnia, Lukić is a man who possibly has more blood directly on his hands than any other individual. There are many for whom the capture of Lukić is third in importance only to that of Karadžic and Mladić. For Lukić - now likely to be extradited to The Hague - the arrest means the end of thirteen long and remarkable years as alleged mass killer, alleged criminal gangster and someone said to have enjoyed, but lost, the cover of both the Serbian state and the network that protects Karadžic himself.

The atrocities of 1992, which rid Višegrad of some 14,000 Muslims - put to flight or to death - remained the secret of scattered survivors for a long time. Years passed before Lukić's name first appeared in public, in The Guardian, which in early 1996 was invited to meet some survivors of the fall of Muslim enclaves at Srebrenica and Žepa, evacuated to a mental hospital in Dublin. Among them was a teenager called Jasmin R, who had fled Višegrad to Žepa in 1992, but was too young to fight. His duty, he said, was to help haul bloated corpses from a lonely junction between the Drina and Žepa rivers, for burial. Which bodies? The ones, he said, from the bridge at Višegrad. With a man called Mersud, he brought the bodies in by small boat, at night, to avoid sniper fire. ‘We dug the graves,’ he said calmly, ‘and buried 180 people.’ Later investigations established that about one body in twenty that floated by was rescued.

The search for Lukić began by locating Mersud himself, who confirmed Jasmin's story and knew and remembered Lukić well; he had ‘seemed a good guy’ during peacetime. It then emerged that in June 1992 a Višegrad police inspector, Milan Josipović, had received a macabre complaint from the manager of Bajina Bašta hydro-electric plant across the Serbian border, asking whoever was responsible to please slow the flow of corpses down the Drina. They were clogging up the culverts in his dam, well down river from Jasmin's and Mersud's Žepa graveyard.

Witnesses to the slaughter were tracked down, across Bosnia and Europe. All recalled a red Volkswagen Passat car (which Lukić had coveted, whose owner he was said to have shot and which he had commandeered) present at the scene. Fehida D, from her balcony, watched ‘Lukić, in his Passat, and the trucks behind, arrived on the bridge each evening. Sometimes they would throw people off alive, shooting at the same time.’ Hasena M, who escaped execution and ended up in a forced labour camp, had crouched near the bridge and ‘watched them put my mother and sister astride the parapet, like on a horse. I heard both women screaming, until they were shot in the stomach. They fell in the water - the men laughing as they watched. The water went red.’

Zehra T, her face and hands deformed by fire, recalled her escape from a house at Bikavac, into which some 70 people had been locked and burned to death, corralled there, she said, by Lukić and others. Esma K recalled being taken to another house, and imprisoned. ‘The Passat arrived at 5pm,’ she said, and within four hours ‘the sky was light because the house was in flames’. She had escaped through a window.

Unfinished work

There were others, but not many. Indeed, there are not many Muslims who remained during that late spring left to remember. Even at the war's end in 1995, one Muslim soldier recalls, at the fall of Žepa, Lukić patrolling the columns of surrendering troops, calling: ‘Anyone from Višegrad, step out of line!’ Even then, his work was unfinished.

The Guardian's account of the blood-letting was published in March 1996, and Milan Lukić was indicted by The Hague two years later for ‘extermination of a significant number of Bosnian Muslim civilians, including women, children and the elderly’, along with his cousin Sredoje and another man, Mitar Vasijević, who has been tried and convicted. Accordingly, the next phase of Lukić's life began.

For years, neither Bosnian Serb nor Serbian authorities showed an inclination to hand Lukić over. He was seen around Višegrad and Serbia, owning an apartment in Belgrade. He was repeatedly charged with racketeering and other organised crime, arrested three times in Serbia - but each time released.

While The Hague sought Lukić, subject to their rules of secrecy, so too did the entwined Sarajevo-based journalistic enterprises, the Institute for War and Peace Reporting and Balkan Investigative Reporting Network. In April 2004, IWPR/BIRN published an account, based on Bosnian Serb intelligence sources and confirmed by Bosnian state intelligence, of what Lukić had been up to.

The report linked Lukić to fugitive leader Radovan Karadžić in two ways: one, he was allegedly part of a lucrative drug-smuggling ring connected to Karadžić's business network. The profits funded a second connection: the elusive and armed Preventiva network which protects Karadžić - and which also provided cover for Lukić. And Lukić was doubly protected: his cousin and patron Sretan Lukić was deputy interior minister of the Serbian state, effectively chief of police.

But around January 2003 Lukić and the Preventiva quarrelled - there were even reports of a shoot-out with Karadžić's guards. The fallout meant that Lukić was at risk on Bosnian Serb soil, even in Višegrad.

Then, in March, came a second blow. Cousin Sretan was indicted by The Hague, removed from his Serbian ministerial post and subsequently deported to face trial. And then a third: in April, police from the ‘Republika Srpska’ entity of Bosnia stormed Lukić's family home in Višegrad in a raid connected to ‘narcotics and smuggling’. By mistake, they shot dead not Milan Lukić, but his innocent brother Novica.

Overtures to The Hague

Lukić, no longer safe, reportedly made overtures to The Hague, with a view to surrender and cooperation over finding and convicting Karadžić, and for his own safety. But he twice failed to show at attempted rendezvous with the tribunal's tracking team. In September 2003 - with pressure mounting on Serbia to cooperate with The Hague and as a sign that the wind had changed direction for Lukić - a court in Serbia sentenced him in absentia to 20 years in jail for the execution of 16 Muslims taken from a bus on the Bosnian-Serbian border in 1993.

By the time of the IWPR/BIRN report in April 2004, Lukić had vanished from Višegrad and his usual haunts in Serbia. He resurfaced in an impenitent email from a server in Brazil. He said those suggesting he was ‘a traitor to Radovan Karadžić’ were speaking ‘a shameless and unscrupulous lie’. While insisting that he was ‘never ... close enough [to Karadžić] to know what his movements were’, Lukić nevertheless pledged that ‘Mladić has always been and will remain the true hero and idol, and Karadžić the leader of my people’.

Lukić told Argentinian judges that he had been in Brazil, entering Argentina on a false passport bearing the Serbian name of Goran Đukanović. He said he was preparing to surrender to The Hague, implying that this was for his own safety, and that he feared people on his own side, Karadžić's people. He told the court: ‘I know lots of things happened during the war, and I was afraid that they would kill me because there are many who do not want it known what happened. As the saying goes: better to be a tongue without a voice.’

This article appeared in The Guardian (London), 11 August 2005, with additional reporting from Uki Goni in Buenos Aires.