On Thursday night, American forces raided a house south of Mr. Hussein's hometown, Tikrit, capturing nearly a dozen people suspected of being his personal bodyguards and enhancing the allies' chances of finding the deposed dictator, officers said. In a second operation, soldiers seized more than 45,000 sticks of dynamite.

"I believe that we continue to tighten the noose, and I believe that we continue to gain more and more information about where he might be," Maj. Gen. Raymond T. Odierno, commander of the Army's Fourth Infantry Division, said from Tikrit in a video teleconference at the Pentagon.

The seizure of the suspected bodyguards provided another lift to American military commanders in Iraq, who said the killing of Uday and Qusay Hussein in a fierce shootout on Tuesday in the northern city of Mosul had coincided with a surge in tips from Iraqis offering information about suspected supporters of Mr. Hussein. 

"It is fair to say that we are seeing an increase in people coming forward," said a military official in Baghdad, who spoke on condition of anonymity. "But it's too early to say why. They may feel more confident now that the threat has been removed."

General Odierno said that of the 13 people seized in the raid south of Tikrit, "somewhere between 5 and 10 of those — we're still sorting through it — are believed to be Saddam Hussein's personal security detachment." He said interrogators had just started questioning the suspected bodyguards, and it was unclear how recently they might have been with Mr. Hussein.

Their capture is significant because it occurred so near to Mr. Hussein's hometown, an area where many people claim a fierce loyalty to Mr. Hussein, and on whom he lavished money and resources during his long rule. In April, on the eve of his 66th birthday, Tikritis poured into the streets to celebrate.

Even before the deaths of the two sons, General Odierno said, the number of Iraqis passing along information to American forces had been increasing in the last two to three weeks. "They are coming in," he said. "And it's because they feel confident we will action on it."

An officer with the 101st Airborne Division, which led the assault on the Hussein sons' safehouse on Tuesday in Mosul, said more informants were coming forward in his unit's area.

"We have had a large number of tips as well," the officer said in an e-mail message. "We have also been conducting an increasing number of raids, partly because of the tips and partly in response to the recent successful attacks against our soldiers."

General Odierno, a native of Rockaway Township, N.J., described in detail a second major raid.

"Last night, we had an Iraqi walk into one of my brigade headquarters and say, `I know where there's a cache of weapons,' " he said. "He gave us the grid. He said, `There's a house, and then 200 meters from that house, there is a container buried under the ground.' So we sent our patrol out there."

At a house in the town of Samarra, south of Tikrit, the search party turned up 10 AK-47 assault rifles, 34 grenade launchers and 150 rounds of ammunition for them, 80,000 feet of demolition cord, 45,000 sticks of dynamite and assorted firearms, General Odierno said. 

He said attacks against the 27,000 Army forces under his command, in a region that ranges from outside Baghdad north to Kirkuk and east to the Iranian border, had been cut in half in the last month because of incessant pressure by military patrols and the capture of 1,000 Baath Party supporters, foreign fighters and other guerrillas. 

"We've taken out some of the midlevel leaders that helped to organize them locally," he said.

But General Odierno warned of possible car bombings and suicide bombers, and said that while attacks were fewer in numbers, they were becoming more sophisticated. He said the guerrillas were using remote-controlled bombs that could be detonated from about 500 yards away, and wire-controlled explosives that could be set off from more than a mile away.

Officers in other divisions concurred. "The lethality and sophistication of the attacks has increased in the past week," said the officer assigned to the 101st Airborne Division. "All the intel folks are scrambling to figure out whether this is in retaliation for killing Uday and Qusay, a change in tactics or something else. The culture really values the concept of `an eye for an eye."

General Odierno said the attacks had been organized locally, not nationally, but were the work of guerrilla groups that had specific hierarchies.

"We do believe there's somewhat of an organization," he said. "There is a very local level where there's a guy who has money, there's somebody who's responsible for caching weapons, and there's a guy who pays individuals to do attacks on American soldiers."

Die-hard supporters of Mr. Hussein are also stepping up their attacks against "softer targets," nonmilitary ones like civilian Iraqis who are cooperating with the allies.

"We see this more as a desperation move," General Odierno said. "And I think in a way, it's backfiring, because we've found when they do this, it's causing more Iraqis to come in and give us information."

As for prospects of finding Mr. Hussein, "we continue to police-up individuals that have a relationship with him," the general said, adding that American forces had even talked to one of Mr. Hussein's former wives about where he could be hiding.