Updated

Iraqi rebels in Fallujah told negotiators Saturday they would agree to hold cease-fire talks there if the U.S. pulled its forces out of the besieged city and held all troops back at least three miles from its border, according to a report from Reuters.

Negotiations have been handled by several members of the Iraqi Governing Council (search) who were meeting with Fallujah city leaders in an attempt to win the handover of people who killed and mutilated four American civilians last week. Governing council members also wanted the insurgents to give up foreign militants in the city, council member Mahmoud Othman said.

Fierce battles raged elsewhere in central Iraq, including Baghdad. Forty Iraqis were killed, two U.S. service members and two Germans were missing, an American civilian was captured and a Red Crescent official was gunned down.

Meanwhile, Brig. Gen. Mark Kimmitt said a third battalion of Marines and a battalion of troops from the new Iraqi army were being moved to Fallujah to join the siege of the city. Two battalions of 1,200 Marines are already in place.

Kimmitt said the military was seeking a cease-fire during the talks, but that insurgents continued to shoot at the U.S. troops. Explosions and sporadic gunfire continued to be heard Saturday afternoon in the city. The Marines largely remained in the industrial zone they hold in the eastern part of the city, 35 miles west of Baghdad.

Some Marines moved a few blocks into a nearby neighborhood, breaking into homes, witnesses said, in an apparent attempt to clear out gunmen firing on them. An AC-130 gunship airplane raked insurgent positions with gunfire Friday night.

Members of the Governing Council have expressed increasing anger over the U.S. siege, calling it a "mass punishment" for the city's 200,000 residents. A Shiite member suspended his council seat in protest, and a Sunni council member said he would quit if the Fallujah talks fell apart.

In Baqouba, northeast of the capital, gunmen attacked government buildings and police stations, fighting U.S. troops in battles that killed around 40 Iraqis and wounded several Americans, said Capt. Issam Bornales, spokesman for the 1st Infantry Division's 3rd Brigade.

Insurgents also fought U.S. troops in Baghdad's northern, mainly Sunni neighborhood of al-Azamiyah.

Guerrillas attacked a tank on a highway near the airport in western Baghdad on Saturday, setting it on fire. In the west of the city, a convoy of supply trucks being escorted by two U.S. Humvees was attacked. One of the trucks was set ablaze and the driver kidnapped, said Majid Hameed, a witness. The kidnapping could not be confirmed and the driver's nationality was not known.

In the north of the country, the head of the Iraqi Red Crescent's Irbil office, Barzan Umer Mantik, and his wife were attacked and killed Saturday in their car in the nearby city of Mosul, the International Committee of the Red Cross (search) said.

Two U.S. servicemembers and several contract employees were still unaccounted for from attacks on Friday, a Pentagon spokesman, Lt. Commander Dan Hetlage, said Saturday.

In the latest in a string of kidnappings this week, Australia's ABC television (search) showed an American civilian being taken away in a car by fighters after an attack on a fuel convoy near Baghdad on Saturday. The man spoke with a southern American accent and identified himself to the camera.

When asked by an ABC reporter what happened, the man said: "They attacked our convoy. That's all I'm going to say."

The car then drove off down the highway with him still in the back seat, passing a burning tanker truck on the road. The prisoner wore what appeared to be a light flak jacket of the sort worn by private security guards, who are often contracted to protect convoys.

Also Saturday, the German Foreign Ministry said two security agents from its embassy in Baghdad have been missing for several days. It gave no further details, but Germany's ZDF and ARD television reported that the missing were two Germans, 38 and 25 years old, who were ambushed Wednesday while on a routine trip from Amman, Jordan, to Baghdad.

ARD said the two were agents with GSG-9, a counterterrorism unit trained for freeing hostages and other commando missions.

Militants kidnapped three Japanese civilians earlier in the week and have threatened to burn them alive unless Tokyo withdraws its troops from Iraq by Sunday, a demand Japan has rejected. A Canadian and an Arab from Jerusalem have also been kidnapped.

A group calling itself the "Marytr Ahmed Yassin Brigades (search)" in Ramadi claimed to have 30 hostages from the United States, Japan, Spain and Bulgaria. A masked man holding an automatic weapon made the claim in video shot by Associated Press Television News. No hostages were shown, and there was no way to verify the claim.

In the south Saturday, the militia of radical Shiite cleric Muqtada al-Sadr (search) remained in control of Karbala and nearby Najaf and Kufa.

Leaders of al-Sadr's militia said Saturday that they would not launch attacks on U.S.-led coalition forces in Karbala, 65 miles south of Baghdad, until the end of a religious festival this weekend.

Hundreds of thousands of pilgrims are in Karbala and other Shiite cities to mark al-Arbaeen, the end of the mourning period for a 7th-century martyred Shiite saint. Ceremonies are to be held until Sunday night.

In their first major military move into south in months, about 1,000 U.S. troops backed by tanks swept into the city of Kut on Wednesday to push out al-Sadr militiamen who had seized control. Kimmitt said al-Sadr followers were driven from much of Kut in the initial assault, and he expected the rest of the city to be under U.S. control soon.

Italian Prime Minister Silvio Berlusconi, meanwhile, made a surprise visit to Italian troops in the southern city of Nasiriyah, which saw fighting with al-Sadr followers earlier in the week but has largely calmed since.

The U.S. military's death toll from the week of fighting stood at 46 after the killing of a Marine on Friday in Fallujah. The fighting has killed more than 460 Iraqis — including more than 280 in Fallujah, a hospital official said. At least 647 U.S. soldiers have died in Iraq since the war began in March 2003.

The Associated Press contributed to this report.