Iraq's health ministry said on Friday up to 150,000 people have died since the 2003 US-led invasion, as outgoing US Defence Secretary Donald Rumsfeld acknowledged the problems in fighting insurgents.
While the country's Shia and Sunni Arabs attended weekly prayers amid a relative lull in violence, clerics from the majority sect called for the speedy execution of former dictator Saddam Hussein.
In violence on the ground, a powerful blast killed an Iraqi army colonel and his five bodyguards in the northern town of Tall Afar.
Back-pedalling on its earlier estimates, the health ministry said that between 100,000 and 150,000 people have been killed since the invasion which toppled Saddam.
It earlier said 150,000 people had died, as reported in the media quoting Health Minister Ali al-Shamari on Thursday during a visit to Vienna.
"The minister was misquoted. He said between 100,000-150,000 people were killed in three-and-a-half years," an official with the ministry said after having initially confirmed the higher figure.
He said the victims were killed "during military confrontations, assassinations and sectarian assassinations," adding that another 70 to 80 people were dying in violence each day.
The ministry had started keeping records only since early 2004, the official noted, effectively meaning that those killed during the actual invasion and in the ensuing months were not included in this figure.
The number of dead in Iraq has been a controversial topic of repeated speculation. Most estimates, such as those by the Iraq Body Count project, have put the figure at between 50,000 and 60,000.
In October, British medical journal The Lancet published a report estimating that 650,000 people had actually died since the invasion, based on extrapolations from people interviewed.
The figure has been dismissed as wildly exaggerated by the Iraqi government, press agencies and the US military, which itself will not release data on civilian casualties in Iraq.
The bulk of the dead in the past year have been killed in a bitter Shia-Sunni sectarian conflict across Iraq. Baghdad has been the worst hit, with dozens of bodies found on the streets every week.
In his first speech since being ousted after his Republican party was defeated in mid-term congressional polls, Rumsfeld on Thursday acknowledged that US efforts to stabilise Iraq have not gone well.
Iraq had made tangible progress, the outgoing defence secretary said, but the sectarian violence and the killings of Muslims by extremists had created "a much more complex situation."
"And quite honestly, our country does not have experience attempting to impose control and our will over vicious, violent extremists that don't have armies, that don't have navies, don't have air forces and operate in the shadows," he said.
On Friday the US military announced the death of another three servicemen, raising the total killed since the invasion to 2,839, according to an AFP count based on Pentagon figures.
Meanwhile, in their Friday prayers a number of Shia clerics called for the speedy execution of Saddam, saying it would end the reign of terror currently gripping Iraq.
Sheikh Ahmed al-Safi, a representative of top Shia cleric Ayatollah Ali al-Sistani, urged that the former Iraqi leader be executed in the Shia holy city of Karbala itself.
"I wish to hang Saddam between the two shrines in Karbala," Safi said at the shrine of Imam Hussein.
Karbala, one of Iraq's two Shia holy cities, contains golden-domed shrines to revered Shia imams Hussein and Abbas.
"Injuries will not heal unless the scaffold is placed here to carry out the sentence," said the representative of Sistani, the most influential Shia cleric in Iraq.
From the holy city of Najaf, Sadr al-Din al-Qubanshi demanded "accelerating the execution".
"Cut the head of the snake and the terror will end," he said as devotees shouted "execution is the least punishment for Saddam!"
On Sunday, Saddam was sentenced by the Iraqi High Tribunal to death by hanging for crimes against humanity, a decision applauded by Iraq's Shias and Kurds but condemned by many in the formerly dominant Sunni community.
Prime Minister Nuri al-Maliki, a Shia, has reaffirmed Iraq's right to hang Saddam, despite international criticism, and said he expected the execution to take place by the end of the year.
In violence on Friday, an Iraqi battalion commander, Colonel Abdul Karim Jassem, and five bodyguards were killed in an explosion at a checkpoint in Tall Afar that also wounded 10 other soldiers and four bystanders.
The northern town was held up by President George W. Bush as a success story in March, but has since been hit by a number of large blasts by insurgents.
Three members of a family were shot dead by gunmen in Baquba, north-east of Baghdad, while another was kidnapped. A police officer from Baghdad's Sunni neighbourhood of Sulaikh was also kidnapped by gunmen.
An Iraqi court sentenced to death a Saudi accused of participating in the insurgency in Iraq, while a Syrian was sentenced to 15 years imprisonment for a similar crime.