WASHINGTON -- The U.S. military said Wednesday that the fifth and final brigade of the so-called troop surge ordered by President George W. Bush has arrived in Baghdad and should be fully operational by mid-July.

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The news comes as the White House stepped back a little from earlier reports about U.S. troops being stationed for years in Iraq, in a manner similar to that of South Korea.

"We are starting to see a shift in momentum that comes with having additional forces on the ground," said Army Brig. Gen. Perry Wiggins.

The troops are tasked with trying to clamp down on the violence in Baghdad's northern and southern belts.

"What we're trying to do through the 'clear, hold and retain' (strategy) is take those particular areas away from the insurgents and al Qaeda, make it more difficult for them to travel, at least freely," he said. "So some of those forces will stretch in Baghdad."

Iraqi and coalition forces captured 47 suspected terrorists, including some suspected terror-cell chieftains, and seized contraband weaponry during operations across Iraq over the past few days, military officials reported Wednesday.

A capture of alleged weapons traffickers in Sadr City is sure to disrupt the flow of weapons into Iraq, officials said.

Army Gen. David H. Petraeus, commanding general of Multinational Force Iraq, is slated to update military and civilian leaders on the Baghdad security plan's progress in September.

White House Hedging On South Korea Model

Meanwhile, in Washington, White House spokesman Tony Snow hedged a bit Wednesday, after telling reporters that the White House might look to South Korea as a potential model for possible U.S. troop deployment in Iraq.

The comparison with South Korea paints a picture of a lengthy U.S. commitment at a time when Americans have grown weary of the Iraq war and want U.S. troops to start coming home. Bush vetoed legislation that would set timetables for U.S. troop withdrawals, and forced Congress to approve a new bill stripped of troop pullout language.

Asked if U.S. forces would be permanently stationed in Iraq, Snow said, "No, not necessarily." He said that the prospect of permanent U.S. bases in Iraq were "not necessarily the case, either."

"What the president means by that is that at some point you want to get to a situation in which the Iraqis have the capability to go ahead and handle the fundamental matters of security. You have the United States there in what has been described as an over-the-horizon support role so that if you need the ability to react quickly to major challenges or crises, you can be there," Snow said.

When asked directly whether thousands of U.S. troops could be in Iraq for 50 years -- as they have been in South Korea, Snow said, "I'm not making that suggestion. ... But having said that, you don't have a crystal ball; what you do hope is that you get to that point where the United States moves away from primary combat roles as swiftly as possible."