The bodies of two American soldiers kidnapped south of Baghdad five days ago have been found at a roadside, the United States military said today.

An Army spokesman said that DNA tests would be conducted on the men's remains to confirm their identities.

"Coalition forces have recovered what we believe are the remains of the soldiers," Major General William Caldwell told a news conference.

Private Kristian Menchaca, 23, of Houston, and Private Thomas Tucker, 25, from Oregon, were kidnapped when their Humvee was ambushed at a checkpoint near Yusifiyah, in the so-called 'triangle of death' on Friday.

Some 8,000 troops backed by helicopters, divers, boats and fighter aircraft engaged in an extensive search for the men, which ended with the discovery last night, near to the scene of the attack..

As news of the deaths was being broken to the two men's families, a message appeared on an Islamic internet forum in the name of the Mujahedeen Shura Council, a coalition of militant groups, claiming that the soldiers' throats had been cut.

Abu Hamza al-Muhajir, who succeeded Abu Musab al-Zarqawi as leader of al-Qaeda in Iraq last week, was said in the statement to have "slaughtered" the two men.

An official from the Iraqi Defence Ministry, who leaked details of the discovery this morning, said that the men had been "tortured and then killed viciously", but Major General Caldwell refused to confirm the reports.

Yusifiyah, an agricultural area criss-crossed by a maze of canals, is a well-known insurgent stronghold. The latest deaths brought to 2,502 the US military’s losses in Iraq since the March 2003 invasion.

Kidnappings of US service members have been infrequent since the 2003 invasion. Troops patrol only in convoys. Foot patrols, while common in parts of Iraq during 2003 and 2004, have become rare because of roadside bombs, snipers and ambushes.

Mr Menchaca's wife, Christina Menchaca, 18, of Big Spring, said last night that representatives of the military informed her on Saturday that her husband was missing. They told her they were taking "every means possible to find him", she said.

"We're basically just watching the news because no one else knows anything about it, no one has heard anything about it," she told the Dallas Star-Telegram. "We're just going by what the news has to say."

As news of Mr Menchaca's death broke, his uncle, Ken MacKenzie, told NBC television’s Today show: "Because the US government did not have a plan in place, my nephew has paid for it with his life."

In Madras, Oregon, the family of Mr Tucker released a recording of the last phone message the family received from their son. He said: "Be proud of me Mom, I'm defending my country. Tell sis and my nephews hello for me, I'm OK, I'm on my way."

Reports of the discovery of the bodies came amid an upsurge in the number of violent attacks across the country after a relative lull.

Seven people were killed and 18 wounded in a car bomb attack on a second-hand clothes market in Jamila, in the east of the capital. In the city centre another two people died in a roadside bomb near a busy market. A security guard at al-Yarmouk hospital in southern Baghdad was shot by gunmen.

In Basra, where British forces are based, an elderly woman died when a suicide bomber attacked a crowd of disabled people and pensioners queuing for pensions. In Suwayra, 25 miles south of Baghdad, the handcuffed bodies of seven people were pulled from the river Tigris.

The attacks come despite the Iraqi Prime Minister's tightened security in the capital, which the Government says involves up to 40,000 troops.

In a fresh blow to the image of American troops in Iraq, the US Army last night charged three soldiers in connection with the premeditated murder of three Iraqi men in military custody on May 9 during an operation near Thar Thar Canal in Salahuddin province north of Baghdad.

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