Also Wednesday, Iraqi interim Prime Minister Iyad Allawi called for residents of Fallujah to hand over militant Abu Musab al-Zarqawi, a rebel leader whose group is linked to many kidnappings and beheadings of foreigners.
Two U.S. soldiers died when a suicide bomber drove his car into a U.S. convoy Wednesday afternoon in the northern city of Mosul.
Before dawn the same day, a roadside bombing killed another U.S. soldier. Three more soldiers died late Tuesday when a bomb exploded in their convoy in eastern Baghdad, the Associated Press reported.
The deaths come as U.S. and Iraqi forces increased attacks on rebel strongholds before the start of Ramadan, a holy Islamic month.
Last year attacks increased during Ramadan. Extremists believe if they die in a jihad during Ramadan they win a special place in paradise, according to the AP.
U.S. forces have also increased aggressive strikes west of Baghdad to try to secure rebel strongholds ahead of January elections.
As Ramadan nears and attacks continue, Allawi made a strict demand to residents of Fallujah to hand over rebels.
"If Zarqawi and his group are not handed over to us, we are ready for major operations in Fallujah," Allawi told Iraq's interim national council. "I hope they (people in Fallujah) will respond. If they don't, we will have to use force."
Air strikes in Fallujah have targeted buildings used by al-Zarqawi. The United States has offered a $25 million reward for information leading to his capture or death. A strike on a Fallujah district ordered by U.S. troops killed eight people Tuesday.
Allawi's demands came soon after Fallujah's chief negotiator expressed optimism about striking a deal.
"We are very close to reaching a final settlement. Our main condition is that the U.S. Army does not enter Fallujah," said Khaled al-Jumali, a Sunni cleric who belongs to the Mujahideen Shura or council, the AP reported.
Later Wednesday a group connected to Zarqawi beheaded two Iraqi intelligence officers captured Sept. 28 and posted video of the killings on the Internet, Reuters reported.
"I advise my brothers, the sons of Iraq, who are working for the government agencies, in intelligence, the armed forces and the police to repent," one of the men in the video said.