THE HAGUE, Netherlands (AP) _ In passing judgment on six Croats accused of attacking a village some of them once called home, the Yugoslav war crimes tribunal has had to grapple with one of the central questions of the Balkan conflict: how friendly neighbors became blood enemies.

In its largest trial yet, the U.N. tribunal was expected to decide today whether the defendants are guilty of taking part in a killing spree in the central Bosnian village of Ahmici.

The six stand accused of belonging to bands of armed Croatians who descended on the central Bosnian village and killed at least 103 Muslims, including 33 women and children, on a spring day in 1993.

Entire families were gunned down, scores of houses were torched, and two mosques were destroyed.

Though the defendants were rank-and-file militiamen, some had grown up in Ahmici and lived alongside those they are accused of assaulting.

After 16 months of hearings and testimony from 158 witnesses in the trial, the tribunal was to pass verdicts on brothers Zoran and Mirjan Kupreskic; their cousin, Vlatko Kupreskic; and Vladimir Santic, Drago Josipovic and Dragan Papic.

If convicted on charges of war crimes and crimes against humanity, the men face up to life in prison in one of several European countries that have offered to incarcerate Balkan war criminals.

The U.N. court has handed down eight convictions since its establishment in 1993. Seven of those convictions are under appeal, and only one convict has served out his term in Norway.

The trial is the tribunal's largest in terms of the number of defendants, but is just one of five in a series known as the ``Lasva River Valley Indictment.''

According to the indictment, Bosnian Croat militia conducted ``a highly coordinated military operation'' to empty the area around the valley of Muslim inhabitants.

The trial of Gen. Timohir Blaskic, commander of Croatian forces in the area, finished last July, but no date has been announced for a verdict.

Muslim villager Sakib Ahmic testified that he had watched the Kupreskic brothers ``grow up into decent people'' until the fighting broke out in the village.

On April 16, 1993, the Kupreskics broke into Ahmic's home and murdered his son Naser and daughter-in-law Zehrudina, as well as their children Elvis, 4, and Sejad, 3, he said.

Ahmic said he was forced to watch the horror unfold, and suffered severe burns when the attackers set fire to the home and fled.

Norwegian anthropologist Tone Bringa, who spent eight years studying interethnic relations in rural Bosnia, was called as an expert witness.

Before the war, she said, Muslim Bosnians and their Roman Catholic Croat neighbors had been ``aware of their religious differences, but were tolerant towards them.''

However, propaganda by nationalist leaders and reports of violence elsewhere in the former Yugoslav republic sparked fear and suspicion, she told the court in July.

``As Yugoslavia disintegrated, and the national ideology took over, the understanding of neighbors of different faith underwent a gradual change,'' she said.

In a separate case, an appeals court begins hearing today the case of Bosnian Serb Dusan Tadic. In the tribunal's longest running case, dating back to April 1995, Tadic is accused of murder, torture and rape in an ethnic purge by Serb forces in northwest Bosnia in 1992.