Outrage of human rights groups over prisoner abuse in Iraq as death toll of US soldiers mounts. The US-led coalition faced outrage Sunday amid mounting allegations of widespread abuse at its jails in Iraq and growing anger from the people it claims to have liberated. Human rights groups demanded an independent inquiry after allegations that US military intelligence ordered the abuse to extract information from Iraqis detained since the March 2003 invasion of Iraq. As anger grew in Iraq and across the Arab world at the graphic pictures of demeaning and sexual abuse, the killing continued fewer than two months before the planned handover of sovereignty to the Iraqi people. Despite the continuing violence, a United Nations team has arrived in Iraq to prepare for elections scheduled for early next year. UN special envoy Lakhdar Brahimi is due in the country later this week as he struggles to find agreement on how the first post-Saddam Hussein government might be formed. Four US soldiers have been killed since Friday evening in the latest attacks, according to a senior military official. Two died in an attack on a convoy at Amara, 365 kilometres (220 miles) southeast of Baghdad, on Friday and another two were killed early Saturday in the capital. The weekend's casualties take the US military death toll to 744, including 542 killed in combat, since the US-led coalition invaded Iraq in March last year. More than 10,000 Iraqis are also estimated to have been killed. Three Iraqis were killed and eight wounded during clashes between British troops and followers of the radical Shiite cleric Moqtada Sadr near Amara Saturday, according to hospital sources. Sadr, who is wanted over the murder of a rival cleric last year, remains holed up in the holy Shiite city of Najaf and remains a key problem ahead of the June 30 deadline for the transfer of limited sovereignty to Iraqi authorities. In the Sunni flashpoint city of Fallujah, 50 kilometres (30 miles) west of Baghdad, hundreds of former Iraqi soldiers have arrived as part of tentative moves to end weeks of fighting there. The head of the Iraqi force, Major General Jassem Mohammed Salah, was greeted amid scenes of jubilation in the shattered city Friday as fighters celebrated victory after US forces withdrew from positions within the city. The US military denied it had been a withdrawal and a senior official on Sunday did not rule out similar Iraqi teams taking responsibility for other parts of the country to try to reduce fighting. However, publication of the graphic pictures of abuse involving British and US troops has thrown into disarray coalition plans to "win the hearts and minds" of the Iraqi people. There were growing indications Sunday that the abuse was more widespread than the coalition has previously admitted after US television network CBS aired the images of the abuse at Abu Gharib prison outside Baghdad. The images depicted prisoners, some naked, in humiliating, sexually suggestive poses. Some of the pictures showed US military personnel pointing and laughing at prisoners. The US military says the abuse involved up to 20 prisoners and has launched three separate inquiries. Six coalition personnel have already been charged with a series of criminal offences. "The very fact we are running an investigation concerning the interrogation procedures out there would indicate there are questions that have arisen as part of this investigation that leads us to other areas," a senior military spokesman said here Sunday. British tabloid the Daily Mirror published a front-page picture on Saturday showing British troops apparently urinating over a hooded Iraqi prisoner in a camp near Basra in southern Iraq. Sunni Muslim leaders in Iraq said the abuse constituted war crimes and there were widespread calls for an independent investigation. "There must be a fully independent, impartial and public investigation into all allegations of torture. Nothing less will suffice," said human rights group Amnesty International. "Our extensive research in Iraq suggests that this is not an isolated incident." Brigadier General Janis Karpinski, suspended after her soldiers were pictured mistreating prisoners, denied she knew anything about the abuse in an interview with the New York Times. The US Army Reserve general claimed that military intelligence was responsible for the treatment of prisoners in the cell block involved. **PHOTO CAPTION*** An Iraqi woman walks by US armored vehicles in Baghdad. (AFP)