WASHINGTON -- About 100 U.S. commandos carried out a secretive ground assault in the Taliban stronghold of southern Afghanistan, opening a new phase of the war on terrorism after nearly two weeks of punishing airstrikes, U.S. officials said Friday night.
Officials said the helicopter-borne commandos returned to base after several hours inside the country. There was no word on possible casualties in the raid, although two people were killed when a support helicopter prepared for a potential rescue mission crashed in neighboring Pakistan.
The official, who spoke on condition of anonymity, would provide no details on the operation except to say it occurred early Saturday morning local time.
Earlier in the day, officials had confirmed that special forces were in northern and southern Afghanistan, searching for Taliban targets to strike and searching for Osama bin Laden and his al-Qaida lieutenants.
The use of small numbers of U.S. troops in Afghanistan early Saturday local time marked a shift to a broader range of military activities -- overt and covert -- that President Bush says is necessary to win the war.
Bush, in Shanghai, China, for a summit with Pacific Rim leaders, was briefed about the commando raid Saturday morning by aides. The previous day, he had refused to confirm U.S. forces were in Afghanistan, but said: "Let me reiterate what I've told the American people and the world. We will use whatever means are necessary to achieve our objective."
A Pakistan military official said Friday that American officials informed his government that U.S. special forces will be conducting "hit-and-run" operations in Taliban-ruled areas of Afghanistan in an effort to flush out bin Laden, members of his al-Qaida network and Taliban leaders.
Sen. Carl Levin, chairman of the Senate Armed Services Committee, said Friday night that introducing commando forces into the conflict would impact the Taliban "militarily and psychologically."
"This is going to be a gradual process," Levin, D-Mich, said on CNN's "Larry King Live." "As we're tightening the noose, it seems to me a lot of important things can be done, including the gathering of the support of a number of opposition forces in Afghanistan."
An unspecified number of U.S. special forces were dropped into southern Afghanistan on Thursday, the official said on condition of anonymity. The official said Pakistan was told U.S. forces have been in northern Afghanistan for more than one week.
In preparation for ground action, the USS Kitty Hawk, an aircraft carrier in the Indian Ocean, was loaded with special forces last weekend.
And an Air Force special operations AC-130 gunships began attacking in southern Afghanistan. The high-firepower AC-130s typically give close air cover to forces on the ground or going in for small-unit operations.
Special operations troops such as the Army's Green Berets perform many missions, including assistance to opposition forces and collection of intelligence. Special forces in southern Afghanistan are supporting the CIA's effort to encourage ethnic Pashtun leaders to break away from the Taliban militia, a U.S. official said Friday.
Defense Secretary Donald H. Rumsfeld declined to comment on that.
Rumsfeld did say that the United States was coordinating with rebels in northern Afghanistan as well as other anti-Taliban forces.
"There is good coordination from the air with the ground in some places, particularly in the north," Rumsfeld told reporters who flew with him Friday to Whiteman Air Force Base, Mo., to visit with crews of B-2 stealth bombers. "There is not that kind of coordination as of yet in the south."
In a later session with reporters at Whiteman, Rumsfeld was asked whether the war against terrorism would have to be fought in countries outside Afghanistan in order to be successful.
"There's no doubt in my mind," he replied.
Separately, U.S. officials said the air assaults that began Oct. 7 and continued Friday will intensify soon and focus more directly on front-line troops of the ruling Taliban.
Airstrikes resumed early Saturday in Kabul, with at least eight explosions rattling the city from the northeast.
Afghan forces opposing the Taliban are attempting to take advantage of the bombing and are hoping for additional U.S. military assistance. Rumsfeld said Friday that the opposition forces known as the northern alliance have asked for and received U.S. aid, including ammunition or money to buy it.
Gen. Rashid Dostum, an ethnic Uzbek warlord who is a northern alliance commander, told The Associated Press on Friday his forces have been holding talks with several U.S. military personnel this week near the city of Mazar-e-Sharif, just south of the border with Uzbekistan, where U.S. forces are stationed.
Dostum said his discussions with the Americans centered on delivering humanitarian aid to Dara-e-Suf, an enclave of opposition resistance south of Mazar-e-Sharif.
U.S. Air Force C-17 cargo planes have dropped more than 500,000 ration packages in Afghanistan, but U.S. officials are hoping to make overland deliveries, which could get more aid to the needy more quickly.
Bush administration officials have said repeatedly since the U.S.-led military action began that special operations forces would play an important role in Afghanistan. But because surprise and deception are critical, officials have declined to discuss specifics.