WASHINGTON, Nov. 6 — The top American military commander for the Middle East has created a covert commando force to hunt Saddam Hussein, Osama bin Laden and key terrorists throughout the region, according to Pentagon and military officials.

The new Special Operations organization is designed to act with greater speed on intelligence tips about "high-value targets" and not be contained within the borders where American conventional forces are operating in Iraq and Afghanistan.

Gen. John P. Abizaid, who commands all American forces in the strategic crescent from the Red Sea to the Indian Ocean, decided over the summer to disband two Special Operations missions, Task Force 5 in Afghanistan and Task Force 20 in Iraq, officials said.

Military officers say a broader, regional mission was given to the new force, which has become one of the Pentagon's most highly classified and closely watched operations.

Much about the force, which is commanded by an Air Force brigadier general, remains classified, and Pentagon officials declined to discuss the rules under which the new force operates throughout the region or whether its would require the permission of a foreign government to operate in its territory.

Military officers say that focusing the intelligence, and the Special Operations firepower, within one organization, called Task Force 121, streamlines the effort to use information on these targets and mount an attack.

The new, more flexible force already has shown results, according to Pentagon officials and military officers, who say it has gotten close to Mr. Hussein. Officials declined to give any details.

The decision to create the force was prompted by several factors, Pentagon and military officials said.

Senior Bush Administration officials are frustrated that Mr. Hussein is on the loose and still exerts influence in Iraq. At a minimum, officials say, Mr. Hussein's mere survival is inspiring attacks on American troops and Iraqi security forces; some officials believe he is playing a role in coordinating and directing the violence by his loyalists.

"Capturing Saddam Hussein or killing him would be very important," Defense Secretary Donald H. Rumsfeld said last week during a speech in Washington. "So we do need to catch him and I think we will."

Mr. Rumsfeld, who routinely cautions that the American military is not designed for manhunts, also said that some of the Iraqi population may be withholding support for the new, American-appointed government in Baghdad because of fears Mr. Hussein may return to power.

"The fact that he's alive is unhelpful," Mr. Rumsfeld said. "Let there be no doubt that the intimidation factor in that regime was near total."

One senior military officer at the American-led coalition headquarters in Baghdad said of the quest for Mr. Hussein, "It's a 24/7 job."

The creation of the task force also reflects a desire by senior administration officials and top military officers to ensure that the American commitment in Iraq does not detract from the hunt for leaders of Al Qaeda and the Taliban who went underground after the war in Afghanistan. Some are believed to be plotting a fresh wave of terror attacks against the United States from the Middle East and the Horn of Africa.

During the wars in Iraq and Afghanistan, the military worked closely with the Central Intelligence Agency, whose officers routinely traveled and lived with Special Operations units. The new task force receives information from the government-wide intelligence community and, like the two previous missions in Afghanistan and Iraq, has C.I.A. officers attached. However, nothing in the mission of the new task force would compel the C.I.A. to halt any of its own operations against terrorists.

While it is unclear whether President Bush, or the newly-formed Iraq Stabilization Group at the National Security Council, were directly involved in the decision to create the new force, senior administration members have said in the last two months that capturing or killing Mr. Hussein would change the dynamic of the American occupation.

Administration officials say politics is not in their equation, but success in finding Mr. Hussein would no doubt be viewed as a significant victory by a large part of the public.

American military, intelligence and law enforcement personnel have begun or participated in anti-terror operations outside of Afghanistan and Iraq, most notably raids in Pakistan to arrest terror suspects and a Predator strike in Yemen against men said to be Qaeda operatives.

Although the task force has not been publicly disclosed, a number of Pentagon officials and military officers agreed to discuss its work in broad terms as an example of the military's new thinking on how to fight terrorism.

The joint task force of elite Special Operations forces from the Army, Navy and Air Force is supplemented by a sizeable conventional force, which might be called upon to secure the perimeter of an area where a raid is about to take place, create a large diversion or bring firepower in greater numbers than the small Special Operations teams.

Commanders realized they were wasting forces by having two complete sets of fighters on alert 24 hours a day for quick-response missions. In addition, tracking and then capturing or killing Qaeda and Taliban leaders or fleeing members of the former Iraqi government required planning and missions not restricted by lines on the map of a region where borders are porous.

Officials described the force as a antidote to those who were concerned that the war to topple Mr. Hussein had taken the military's eye off the other prizes: capturing Mr. bin Laden and Qaeda leaders, as well as Mullah Muhammad Omar, the fugitive Taliban commander, and Gulbuddin Hekmatyar, an anti-American Afghan warlord who survived an attack in 2002 by a Hellfire missile launched from a Predator reconnaissance aircraft.

While American forces have captured or killed many of the top members of Mr. Hussein's government they have had less success with Taliban and Qaeda leaders who survived the war in Afghanistan.

The United States "has made somewhat slower progress tracking down the Taliban — Omar, Hekmatyar, etc.," Mr. Rumsfeld said last month in an internal memo first reported by USA Today. He added: "We have made many sensible, logical moves in the right direction, but are they enough?"