The top U.S. commanders in northern Iraq predicted Tuesday the battle to oust Al-Qaeda in Iraq from its last urban stronghold will not be a swift strike, but rather a grinding campaign for Mosul that will require more firepower from both the Pentagon and Iraqi allies.

The statements appeared to discount suggestions by Prime Minister Nouri al-Maliki that Iraqi forces were gathering for a "decisive" attack as soon as all reinforcements are in place.

"It is not going to be this climactic battle ... It's going to be probably a slow process," said Maj. Gen. Mark P. Hertling, commander of U.S. forces in northern Iraq.

In a telephone interview from his headquarters in Tikrit, Hertling described the strategy for Mosul — Iraq's third-largest city — as the same step-by-step tactics used in the U.S.-led troop offensives in Baghdad: win control of a district and keep troops there to hold it.

Hertling said he was moving a considerable force of "enablers" into the Nineveh province and Mosul, its capital. He would not disclose numbers, but said the move on Mosul had long been planned.

But attention on Mosul has sharply increased in the past weeks with a rise in insurgent violence, including a bomb cache that tore through a poor Sunni neighborhood, killing about 60 people and wounding more than 200 last week. Then on Monday, U.S. forces were caught in a bomb-and-bullets ambush that killed five U.S. soldiers.

Al-Maliki has promised to send a wave of Iraq police and soldiers into the Mosul area to crush Al-Qaeda and its backers.

The offensive raised the possibility that Iraqi forces were moving toward a critical test by leading the difficult urban offensive in a city of 2 million people. Hertling's comments, however, suggested a heightened level of U.S. involvement and oversight.

Lt. Col. Michael Simmering, of the 3rd Armored Cavalry at Forward Operating Base Marez near Mosul, also described the insurgent force in the city as a patchwork of groups, including Al-Qaeda in Iraq and other factions, "all vying for different things at this point."

"The thing about the insurgency in Mosul is that there are many different facets," he said.

"This is going to be a long, protracted push by coalition forces and more importantly by Iraqi security forces to re-establish security," Simmering added. "If you're looking for one big culminating event, you'll never quite see it. I call this the 'campaign for Mosul."'

Michael O'Hanlon, an Iraq watcher at the Brookings Institution, agreed.

"Al-Qaeda regenerates so it is impossible to say it ever has had or will have a 'last stand,"' he said. "But it is true we can identify and target existing infrastructure and leadership, and that we've been fairly successful in most parts of Iraq except Mosul to date."

That is what Hertling counts on.

"There are some foreign fighters, there are some hardcore Iraqis and there are a bunch of others that I think can be persuaded to fall off of the organization either because they are going to see a lot of their friends killed or they're going to be offered jobs," the general said.

As violence had declined in many parts of Iraq, U.S. reconstruction teams have increased efforts to reopen factories and businesses as a way to further blunt the insurgency.

"I think what you see is once you get young men working again they will quit doing the things that allow them to form into gangs which support these extremist organizations," he said.

At Mosul's airfield, a cold wind blew across the tarmac as pallbearers took turns unloading a flag-draped coffin from the back of five Humvee ambulances carrying the bodies of the soldier's killed in Monday's attack.

Even civilian workers formed an honor line as the dead soldiers' bodies were loaded into a gray C-130 transport plane.

Soldiers refused permission to photograph the ceremony, saying the pain of the sudden loss of five comrades was too great, and that not all the families had been notified.

Later Tuesday, a suicide car bomber targeted another U.S. patrol in Mosul, killing at least one Iraqi and wounding as many as 15, the military and police said. The bomber detonated an explosives-laden car in a predominantly Sunni area in eastern Mosul, a police officer said, speaking on condition of anonymity because he wasn't authorized to release the information.

No American casualties were reported.

In Baghdad, a bombing at a checkpoint wounded five American soldiers and three civilians, the U.S. military said.

The attacker — described as a female suicide bomber — triggered the blast as women were being searched to enter a commercial street in the predominantly Sunni Amariyah neighborhood in southwest Baghdad, according to a local police official and an Iraqi army officer who spoke on condition of anonymity because they weren't authorized to release the information.

But Navy Cmdr. Scott Rye, a U.S. military spokesman, said initial reporting indicated it was not a suicide attack but a bomb that was left at the checkpoint and later detonated. He said no deaths were reported, but five soldiers and three civilians were wounded.

Northwest of Baghdad, Iraqi police said a Sunni leader was killed late Monday when his car exploded after he had met with U.S. forces.

The apparent attack against Abbas al-Dulaimi is the latest against a member of a so-called Awakening Council — Sunni groups that have turned against Al-Qaeda and credited with helping significant U.S.-led gains across central Iraq.