Four US marines were killed in three separate incidents in the restive Al-Anbar province of western Iraq, the US military announced Saturday.
"Three marines assigned to 1st Marine Expeditionary Force were killed in action September 24 in two unrelated incidents, while conducting security and stability operations in the Al-Anbar province," a statement said without elaborating.
Another statement announced the death of a fourth marine in a third incident, also on Friday.
Al-Anbar province includes the Sunni Arab insurgent bastions of Fallujah and Ramadi, as well as the troubled Syrian border district.
Another US soldier was killed Saturday when a roadside bomb blew up in the Baghdad area.
"A Task Force Baghdad soldier died when an improvised explosive device detonated Sept 25. The blast occurred at about 6:45 am (0245 GMT). There were no other casualties as a result of this explosion," a US military statement said.
Based on Pentagon figures, the latest deaths bring to 1,044 the number of US troops killed in Iraq since last year's invasion.
Meanwhile, US aircraft pounded the insurgent enclave of Fallujah on Saturday, killing seven Iraqis in a raid the military said targeted a suspected hideout of a militant group.
Another seven Iraqis -- national guard recruits -- died in a rebel attack near the capital, Baghdad.
In New York, visiting Iraqi Prime Minister Iyad Allawi pledged that the country's own forces would secure his war-torn country in time for January elections to be held.
In the shadowy and bloody battle involving foreign hostages, Britain sent a delegation from the Muslim Council of Britain to seek the release of engineer Kenneth Bigley, threatened with the same death, by beheading, meted out earlier this week to two Americans kidnapped with him.
Bigley, 62, and the Americans were seized from their Baghdad home earlier this month by the Unity and Holy War group of alleged al-Qaeda operative Abu Mussab al-Zarqawi.
A web posting claimed on Saturday that he had been executed but the British authorities dismissed the statement.
"We are undertaking this mission with the hope that there is still a possibility that Mr Bigley is alive, and that there may be some hope that the hostage-takers are holding out for something," said delegation member Daoud Abdullah.
The engineer's family continued to issue desperate pleas for his life, this time asking Dutch Foreign Minister Bernard Bot -- whose country holds the rotating presidency of the European Union -- to make an appeal on the Arab news network Al-Jazeera.
Bot refused, saying such a move would do nothing to soften the captors.
The families of six Egyptians kidnapped recently in Iraq also pleaded for their lives, although no group has yet claimed responsibility for kidnapping the men, all employed by the Egyptian telecom giant Orascom.
"This leads us to estimate that there are no political motivations behind these kidnappings," an Egyptian diplomat in Baghdad said.
The Egyptian government also called for the release of all hostages.
The fate of two missing Italian women, both aid workers, remained unknown, despite two distinct claims that they had been killed.
An Italian daily Saturday published around 40 grisly pictures of beheadings of hostages in Iraq and Pakistan, riding roughshod over the feelings of families and friends of two young aid workers, Simona Torretta and Simona Pari.
Il Foglio said the move was "to protest against the indifference, passivity, ignorance and submission with which the politicians and the media, above all in Italy, are facing up to the religious war and the clash of civilisations going on in the world."
In its daily battle against insurgents, the US military said its air force "conducted a strike inflicting a blow to the Abu Mussab al-Zarqawi terrorist network by conducting a precision strike on a known terrorist meeting site in central Fallujah."
Medics in the town said women and children were among the dead.
The military said other overnight operations in the insurgent-held town, west of Baghdad, were aimed at destroying positions rebels had erected around the city.
Besides the Baghdad attack on national guard recruits in which seven Iraqis died, insurgents in the restive town of Baquba, north of Baghdad, killed a police officer. Police there said they had arrested four Zarqawi operatives suspected of carrying out several attacks in the area.
At least one rocket and three mortar rounds struck Iraq's heavily fortified oil ministry building in Baghdad, causing some damage but no casualties, a spokesman said.
Meanwhile, on a trip to the United States, the Iraqi premier assured the US administration that his forces could secure the country but demanded broader participation from the international community.
"I appeal to all representatives from the countries gathered here to help Iraq defeat the forces of terrorism and help Iraq build a better future for the people of Iraq," Allawi told the UN General Assembly.
Slovakia's Defence Minister Juraj Liska said on Saturday his country had offered to give military instruction to Iraqi soldiers "on our territory".
He acknowledged that Iraqi authorities would prefer Iraqi soldiers to be trained on the spot because "they do not want their soldiers to leave Iraqi territory for a long period." He added he had not given any firm commitment.
US Secretary of State Colin Powell, meanwhile, told the New York Times Allawi wanted to organise a conference including G-8 and Middle Eastern countries in October to boost Iraq's electoral process.
The hawkish premier came under fire for painting what his critics termed an unrealistically rosy picture of Iraq's situation, where ever-worsening violence is impeding progress in reconstruction.
Allawi insisted elections would go ahead as planned, but even US Defence Secretary Donald Rumsfeld acknowledged that the vote might have to exclude no-go zones like Fallujah.
Democratic presidential candidate John Kerry, who has been stepping up his attacks against the US administration's handling of the war in Iraq, on Friday charged Allawi with turning a blind eye to reality in his country.
US President George W. Bush, who had earlier welcomed Allawi to the White House to help spread his optimistic view of Iraq's future, responded: "You can't lead this country if your ally in Iraq feels like you question his credibility."