He said witness accounts collected during a week-long inquiry in Tuzla to which more than 6000

He said witness accounts collected during a week-long inquiry in Tuzla, to which more than 6,000 refugees fled, left little doubt that atrocities had been widespread. "These events require a thorough investigation. But I can say that what happened cannot be described as violations of human rights but as extremely serious violations on an enormous scale," Mr Mazowiecki said."What requires investigation is the scale and dimension, but we can say barbaric acts have been committed," he said. Mr Mazowiecki said the Bosnian Serbs had rebuffed repeated requests from his team to visit areas where thousands of Muslim males were believed to be detained.Dutch UN peace-keeping troops, who were overwhelmed by the Serb onslaught on Srebrenica, said on Sunday after their return to UN mission headquarters in Croatia that they witnessed Serb soldiers executing and mutilating Muslims.Two peace-keepers spotted nine Muslim men being hustled to a building for interrogation and then heard gunfire. They later found and photographed the corpses of the nine men with bullet wounds in their backs, a senior Dutch officer told reporters.The Bosnian Serbs have denied committing atrocities in Srebrenica, but UN sources say that myriad and consistent accusations of summary executions, rape and other abuses made by the refugees appear credible.Dutch soldiers could not confirm allegations that many Muslim women were raped by Serb soldiers after being removed from Serb-run expulsion convoys, but they added they had no way of monitoring the forced evacuation.In Zagreb, UN spokesman Chris Gunness condemned the Serbs for "their inhuman and degrading treatment" of Srebrenica's inhabitants.. The Israeli Prime Minister, Yitzhak Rabin, yesterday suspended the lagging peace negotiations with the Palestinians and stopped all West Bank and Gaza Arabs from crossing into Israel following a Muslim suicide bombing that killed at least five Israelis and wounded 33 on a Tel Aviv bus during the morning rush hour.

The bombing will keep tens of thousands of Palestinians from jobs on Israeli farms and building sites. Mr Rabin spurned the taunts and curses that greeted him when he visited the wrecked bus near the 40-storey Ramat Gan diamond exchange. "They cannot," he said, "distinguish between the new reality, in which we have partners for peace, and those who are still its enemies. We shall not surrender to this mood, however genuine and painful it may be We have to carry on. We will carry on." The leader of the Palestine Liberation Organisation, Yasser Arafat, unequivocaly condemned the bombing, for which the Hamas Islamic movement claimed responsibility, as an act of terror, and sent condolences to the bereaved families.Asked what impact it would have on the negotiations, Mr Arafat told reporters: "It will definitely have an effect.

But I am sure that the wisdom of the Israeli Prime Minister and his Cabinet, with our co-operation, will be able to overcome these obstacles." The Palestinian Economics Minister Ahmed Qureia, a top negotiator, said talks would resume in a day or two.None the less, in a leaflet issued later in the day, Mr Arafat's Fatah organisation suggested that the bombing might give the Israelis a pretext for dragging their feet and for postponing the promised release of 1,000 Palestinian prisoners.The right-wing Likud opposition immediately demanded that Mr Rabin break off the negotiations. The chairman of its parliamentary faction, Moshe Katzav, contended that the government had no mandate for the process. It should, he said, either call an early general election or submit any further agreement to a referendum.Yesterday's operation was the first suicide bombing within Israel since 22 January, when 21 Israelis were killed at a bus stop near the northern resort town of Netanya. Last October another explosion killed 21 Israelis and a Dutch visitor in the heart of Tel Aviv.Israeli opinion has shown itself extremely volatile in the face of such attacks - and to the proposed army evacuation of West Bank Arab towns, which arouses similar anxiety. A poll published last Friday in the tabloid Ma'ariv found Mr Rabin trailing six points behind the Likud leader, Benjamin Netanyahu, in anticipation of this next stage of the peace process.Yesterday's bomber is believed to have entered Israel from the West Bank, an area still under Israeli control. Israel TV broadcast a composite sketch of the suspected bomber based on interviews with witnesses. It described him as bearded, of medium height and athletic build, and between 25 and 30 years old.

Fingerprints of the bomber had been taken and an identification was expected soon.Police said the bomber probably boarded the bus near the Ayalon shopping centre about 2.5 kms (1.5 miles) north of the blast site. "The bus stopped at the light, and I suddenly heard an explosion," said Shlomi Uziel, 23. "People screamed, the windows blew out, and I jumped out the window. I couldn't see anything because my face was full of blood." A driving instructor who was the first to board the bus after the explosion, said it was "filled with destroyed bodies .The head of a girl was still spinning on the floor."The back door hung from the top hinge, part of the ceiling caved in and the seat apparently occupied by the suicide attacker was obliterated.

Body parts lay scattered across wooden seats and on the floor, amid sweet wrappers and a crushed Coca Cola can.Mr Rabin acknowledged the efforts made by the Palestinian security forces to block attacks from the Gaza Strip. He pledged to intensify Israel's own war on terror, indicating that no legal constraints would be placed on the Shin Bet internal security service. This was interpreted to mean that interrogators will be more free to torture suspects.. Yitzhak Rabin has little choice but to continue negotiations with the Palestine Liberation Organisation despite yesterday's bomb explosion. The fate of his government, which faces election next year, depends on Israel making progress in resolving its conflict with the Palestinians. "We will," he insisted after a suicide bomber ravaged a crowded Tel Aviv bus, "solve it, if not tomorrow, then the day after tomorrow.'' Yet every blow of this kind makes his - and the PLO leader Yasser Arafat's - task more intractable. Mr Rabin was elected three years ago on a platform of "peace with security".