Bombs rocked a teeming quarter of Baghdad (search) and a sex-film theater in Mosul (searchon Wednesday, reportedly killing at least three Iraqis and wounding dozens. In a string of ground clashes, the U.S. military said they killed nine Iraqis on one of the bloodiest days of combat in weeks.

The nine deaths were all in the region around Tikrit (search), Saddam Hussein's hometown. U.S. troops aborted two ambushes by anti-American forces, killing five Iraqis, and came under fire elsewhere in exchanges that left at least four Iraqis dead.

The surge in attacks came as world leaders worked to find agreement in New York on how to restore stability to Iraq.

Early Thursday, two suspected Iraqi resistance leaders accused of organizing and financing attacks against U.S. soldiers in the vicinity of Saddam Hussein's birthplace were arrested in raids. Their identities were not released.

The arrests in Tikrit's affluent neighborhoods were part of an intensified campaign against people believed responsible for a series of deadly attacks against U.S. troops.

In Baghdad, communist leader Hamid Majid Moussa said he and other members of the U.S.-appointed Iraqi Governing Council, want to move toward national sovereignty "as fast as we can." But council members refused to be drawn into the debate over a specific timetable.

"We don't want to become involved in fruitless discussions," said Moussa, one of four council representatives at a news conference.

The debate among the United States and other governments over Iraq's future moved this week to U.N. headquarters in New York, where the Bush administration seeks a Security Council resolution encouraging other nations to contribute troops to the Iraq security force.

In exchange, France and others, including Germany, want the resolution to give the United Nations a greater voice in the political transition in Iraq, and a speedy move, in "months, not years," to full Iraqi sovereignty -- that is, to ending the American postwar occupation.

Bush met with German Chancellor Gerhard Schroeder on Wednesday in New York, and both said later they would work to resolve those differences. Schroeder renewed Germany's offer to help train Iraqi police, but reiterated that Germany would send no troops here.

More than five months after the ouster of Saddam's government, the troops who are here -- almost all Americans -- face a daily threat of homemade roadside bombs, mortar attacks and small-arms ambushes.

For the first time Wednesday, U.S. soldiers in central Baghdad were seen deploying bomb-disposal robots, to check a suspicious object in an underpass. That proved harmless, but at about the same time three miles to the northwest, a bomb meant to catch a passing U.S. motorized patrol exploded instead as two buses rolled by.

The blast, in the old Tigris riverside district of Azamiyah, sent shrapnel ripping through the buses and caused one to crash into a tree. At least one Iraqi was killed and 18 were wounded, police and hospital officials reported. Five of the injured were in critical condition, hospital officials said.

In the northern city of Mosul, a bomb exploded in a movie theater showing foreign sex films, and witnesses said two people were killed and seven wounded. Religious and political groups have warned cinema owners against showing such films after censorship ended following the collapse of Saddam's regime.

South of Tikrit, near the town of Balad, seven Iraqis attacked an oil pumping station guarded by troops of the U.S. 4th Infantry Division. The Americans called in an AC-130 gunship, whose heavy weapons fire killed at least three Iraqis, reported division spokeswoman Maj. Josslyn Aberle. A fourth was seriously wounded.

In a second clash near Balad, a U.S. patrol killed three Iraqis waiting in ambush with small arms and rocket-propelled grenades, the military said.

Another U.S. patrol in the same area opened fire on three men trying to bury a homemade bomb -- a mortar shell that was probably to be triggered remotely -- on a highway used by U.S. convoys. Two Iraqis were killed in the firefight, Aberle said.

In a fourth firefight south of Tikrit, American soldiers came under fire, pursued the attackers to a house, and killed one Iraqi, the military said.

Aberle also reported U.S. troops arrested an Iraqi thought responsible for blowing up an oil pipeline last week. That attack, near the town of Beiji north of Tikrit, damaged a pipeline leading from the oil fields to a storage tank.

It was the first time the military has acknowledged that the pipeline explosion was an act of sabotage.

The Americans have been carrying out near-daily raids in the Tikrit area following a coordinated attack by Iraqi resistance fighters Sept. 18 that killed three American soldiers. The raids have resulted in dozens of arrests.

American and Iraqi officials blame the anti-U.S. resistance on remnants of Saddam's regime. Other Iraqis say some countrymen simply resentful of American domination may be joining in the attacks.

In Washington, the vice chairman of the Joint Chiefs of Staff, Marine Gen. Peter Pace, said the Pentagon may be forced within several weeks to alert large numbers of additional National Guard and Reserve soldiers for Iraq duty if other countries don't soon pledge thousands more troops.

In another development, Iraqi Governing Council members defended their decision announced Tuesday to restrict the newsgathering activities here of satellite television channels Al-Jazeera and Al-Arabiya, for supposedly inciting violence against the Americans and Iraqi officials.

Both stations have broadcast statements purported to be from Saddam and footage showing what were said to be resistance fighters vowing to continue attacks on U.S. troops. "They showed people on TV demanding that members of the council should be killed," council member Iyad Alawi told reporters.

In fact, one council member, Aquila al-Hashimi, was wounded last Saturday in an assassination attempt in Baghdad. She was reported Wednesday to have taken a turn for the worse. "She is gravely ill," Alawi said.