A UN report released overnight said 6,599 Iraqis had died violently in the last two months, 700 more than the previous two, making the period the deadliest yet. Many were tortured and killed by death squads because of their religion, it said.

Italian soldiers stand guard at a checkpoint on the outskirts of Basra in this May 22, 2006 file photo. Italian forces ended their mission in Iraq on Thursday, handing over the southern province they patrol to Iraqis, while the United Nations said the country has become deadlier than ever. [Reuters]

"Bodies found at the Medico-legal Institute often bear signs of severe torture including acid-induced injuries and burns caused by chemical substances, missing skin, broken bones, missing eyes, missing teeth and wounds caused by power drills or nails," the report said.

July was deadlier than August, which Washington say shows a security crackdown in the capital Baghdad is working. But violence has already escalated again in September, with a surge in death squad killings in the capital and a relentless series of bomb attacks in the north and west in recent days.

The latest, a massive car bomb strike on a tribal leader in Samarra, killed 10 and wounded 39 on Wednesday, according to police. On Thursday, gunmen in four cars attacked a police station in western Baghdad, killing six.

ITALIANS DEPART

The withdrawal of 1,600 Italian troops from Dhi Qar province means the two allies that invaded Iraq in 2003 -- the United States and Britain -- are now the only big, rich countries with large forces there.

The Italians, under British command in the southern sector, will all be home within eight weeks, British military spokesman Major Charlie Burbridge said.

The province also includes a giant US air base which will not be turned over, near ruins of the ancient city of Ur. A task force of 450 Australians will stay on that base as a rapid reaction team in case of a security emergency in the province.

Dhi Qar is the second of Iraq's 15 non-Kurdish provinces to be turned over to Iraqis after the Japanese pulled out of mainly desert Muthanna province, also in the south, two months ago.

"This is a great day in Iraq's history," Prime Minister Nuri al-Maliki said at a ceremony in the provincial capital Nassiriya, which featured Iraqi troops parading in bright yellow pickup trucks with machine guns mounted in the back.

"Muthanna was first, now comes Dhi Qar to crown this victory, and other provinces will come to crown further victories until we reach our goal."

The British commander, Major General Richard Shirreff said: "I have great confidence in the security forces in the province. Both police and army are well led, and, most importantly, have good relations with the governor.... I congratulate you wholeheartedly."

Britain has also pulled out of its main base in a third province, Maysan, leaving British troops in the south largely confined to Basra, Iraq's second largest city.

In both Maysan and Muthanna, the bases that were evacuated by foreign troops were promised for Iraqi forces, but were ransacked by looters within hours of the foreigners leaving.

While other countries are pulling troops out, Washington has sent thousands more this year in an effort to stem a rapidly escalating spiral of violence. The US commander in the Middle East said this week there will be no cutbacks before mid-2007.

Washington is now focusing its effort on the capital Baghdad, scaling back its forces in the rest of the country.

US commanders predict violence will get worse next week with the start of the Ramadan holy month, and they say attacks on U.S. troops have also surged in the last two weeks.

Followers of radical Shi'ite cleric Moqtada al-Sadr said US forces had arrested one of Sadr's top aides, Salah al-Obeydi, at his home in the holy city of Najaf.