A shaky truce between US Marines and Sunni Muslim guerillas held in Falluja yesterday after further talks to calm Iraq's bloodiest fighting since the fall of Saddam Hussein.
The US military said two US soldiers and seven American contractors were missing in Iraq, where three Japanese are among foreigners being held by guerillas.
Three Czech journalists became the latest foreigners to go missing. But the official Xinhua news agency in China said seven Chinese nationals kidnapped in Iraq had been released and taken to a "secret place". There was no independent confirmation.
Eleven Russians working for an energy company in Iraq have been kidnapped in Baghdad, Al Jazeera television reported late last night, citing an unnamed Russian source.
The television said its correspondent in Moscow was told about the kidnapping by the Russian company for which the Russians worked.
The American contractors, who worked for US company Kellogg, Brown & Root, went missing after an attack on a US fuel convoy just west of Baghdad on Friday.
A Reuters photographer saw at least nine bodies after the attack. An American seized in the ambush told a television crew that witnessed his abduction he was the only survivor.
Despite some overnight clashes in Falluja, Iraqi mediators said they had secured an extension to a truce that gave the town some respite at the weekend. Mohammed Qubaisi, of the Iraqi Islamic Party, said more talks were expected today.
General John Abizaid, head of US Central Command, told a news conference he had asked the Pentagon for two more "strong and mobile" brigades to be sent to Iraq, but the military denied there was chaos in the country.
US forces, who have been struggling for months to crush a Sunni insurgency in central Iraq, now face a Shi'ite revolt led by radical cleric Moqtada al-Sadr in parts of the south.
"The mission of US forces is to kill or capture Moqtada al-Sadr," Mr Sanchez told the news conference.
The US military said US-led coalition forces had lost about 70 dead and killed about 10 times that number of rebels this month.
The coalition death toll compares to 89 troops killed in action in the three-week war that toppled Saddam. At least 474 US troops have been killed in combat since the war began.
With President George W. Bush seeking re-election in November and Iraq high on the campaign agenda, the US-led administration in Baghdad said it was vital to defeat guerillas before the planned US handover of power to Iraqis on June 30.
"It is critical that we cleanse the Iraqi body politic of the poison that remains after 35 years of Saddam Hussein's totalitarian rule," said spokesman Dan Senor.
"We must confront these forces now. The task will only become more difficult down the road," said Mr Senor.
Mr Abizaid said: "There is not a purely US military solution to any of the particular problems that we're facing here in Iraq today."
Saying there may be purely Iraqi solutions, Mr Abizaid added: "So it's a combination of military and political action both on the Iraqi and the American side, and on the coalition side, that will ultimately work towards a more secure environment here."
US Brigadier General Mark Kimmitt said US Marines were ready to "complete the destruction of enemy forces" in Falluja, unless political negotiations produced results.
Each side blames the other for breaking the informal truce. Mr Kimmitt had no word on civilian deaths in what has been Iraq's most violent period since Saddam was ousted. Rafa Hayad al-Issawi, director of Falluja's main hospital, said he believed more than 600 Iraqis had been killed in the town.
The Marines attacked rebels in Falluja last week in response to the murder and mutilation of four American private security guards ambushed in the town on March 31.
Mr Kimmitt said US-led forces had deployed "a significant amount of combat power" to secure roads west and south of Baghdad. But guerillas struck again, setting a US military truck ablaze on the road to Baghdad airport, witnesses said.
Many Iraqis, including some members of the US-appointed Governing Council, have been shocked at the ferocity of last week's violence in Falluja, 50 kilometres west of Baghdad.
Civilians fleeing Falluja said they were haunted by the violence.
"I could see many bodies in the streets. Hundreds were lying in the street. Relatives were too scared to get them," said Samir Rabee, who escaped Falluja with relatives and eight other families in the back of a refrigeration truck.
In reprisal, insurgents have kidnapped an unknown number of foreigners.
Mohsen Abdel Hamid, a member of Iraq's Governing Council, said 12 hostages had been freed after the Association of Muslim Clerics issued an edict condemning hostage-taking. He did not give the nationalities of those he said had been released.
He said the association had been in talks to secure freedom for remaining hostages. "We hope today the rest will be released, God willing," the Sunni cleric said.
The captors of the three Japanese have threatened to kill them if Japanese forces are not withdrawn from Iraq.