At least 83 US soldiers have now died in October - the highest monthly death toll of 2006.
Three of the soldiers were killed Sunday in insurgent attacks in Baghdad, the US military said, while one soldier and one marine were killed Saturday in the Salah as Din and Al Anbar provinces, the military said Sunday.
Another three US Marines had been killed in fighting in al Anbar province on Saturday, the military had announced.
At least 13 Iraqi police recruits were killed, 25 injured and many others kidnapped in an ambush on two buses near the northern Iraqi city of Baquba, media reports said.
The recruits, all members of the Shiite religious grouping, were on their way back to Baghdad to celebrate the end of Ramadan Monday, according to US broadcast network CNN.
At least seven Iraqis were also killed and dozens injured in violence in and around Baghdad Sunday.
In one incident, a suicide bomber detonated an explosives-laden car as he drove on a main road leading to one of Baghdad's biggest wholesale markets. The blast killed at least two civilians and wounded five.
One person was killed and three wounded when an explosive device blew up in another busy commercial market in southern Baghdad.
In the east of the capital, an explosion injured six civilians and caused damage to nearby shops and cars as it ripped through the Iraqi district.
Also Sunday, a senior US diplomat said the policy of his country in Iraq was marked by "arrogance" and "stupidity," during an interview with pan-Arab channel al-Jazeera.
Alberto Fernandez, public diplomacy director in the Bureau of Near Eastern affairs at the State Department, first claimed he had been misquoted, according to a statement released by the State Department after the interview, but he later retracted his comments.
"Upon reading the transcript of my appearance ... I realized that I seriously misspoke by using the phrase 'there has been arrogance and stupidity' by the US in Iraq," Fernandez said in a statement late Sunday. "This represents neither my views nor those of the State Department. I apologize."
The controversial remarks came as US President George W Bush held meetings at the White House Saturday with his top generals on Iraq amid mounting criticism of the administration's handling of the war in the run-up to November's mid-term elections.
"We tried to do our best (in Iraq), but I think there is much room for criticism, because, undoubtedly, there was arrogance and there was stupidity from the United States in Iraq," Fernandez told Qatar-based al-Jazeera.
Also in the interview, Fernandez said his country was "open to dialogue" with insurgents in Iraq, except for those affiliated to the terrorist group al-Qaeda.
"We all know that, at the end of the day, the solution to the hell and the killings in Iraq is linked to an effective Iraqi national reconciliation," Fernandez said. DPA
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