The World Trade Center "is still burning as we sit here, they're still bringing bodies out. Fortunately, the caves and tunnels at Tora Bora are also burning," said Rumsfeld, the highest level U.S. official to visit Afghanistan in more than a quarter-century.
U.S. forces are working with the Afghan opposition is searching the caves and tunnels in Tora Bora for members of the al-Qaida terrorist organization and their leader, Osama bin Laden.
Rumsfeld, making the first trip by a top U.S. official to this country newly freed from the rule of the Taliban militia, met with the interim prime minister, Hamid Karzai, on Sunday at an airfield bearing the scars of decades of war.
Afghan's incoming government takes office Saturday.
Rumsfeld told reporters that Karzai, the incoming prime minister, "is anxious to be cooperative with us in every possible way."
Nevertheless, "It's not going to be an easy task," to build Afghanistan into a country without factional fighting and inhospitable to terrorists, the defense secretary said. "We want to be as helpful as we can" in that regard, Rumsfeld said he told Karzai.
The defense secretary told reporters traveling with him that it was important for him to meet with the country's new leaders for a chance "to sit down face-to-face to talk abouwhat has been done and what's left to be done - and there's a good deal left to be done."
"We want to make sure that we are all on the same wavelength as to what's left to be done," Rumsfeld said.
Sitting less than a mile from former Taliban front lines, on folding chairs in a room draped with camouflage inside a damaged aircraft hangar, Karzai told Rumsfeld the U.S. military had boosted an opposition "incapacitated" by years of war.
"The way you provided help for us was the opportunity that we wanted," Karzai said.
He said an international security force for Kabul, the capital, would number between 3,000 and 5,000. He said the United States was prepared to offer help to the security force, including providing them with intelligence, airlift support, and a rapid reaction force to protect them if something goes wrong.
Rumsfeld said he was making his trip to the region, which included visits to several former Soviet republics, to meet with Afghanistan's new leaders and to visit U.S. troops and commanders.
He described a conversation with a U.S. special operations soldier, who showed Rumsfeld the saddle he used earlier in the war, as he called in airstrikes from horseback while with northern alliance fighters.
"We get a chance to talk to real people who are doing real things that are part of our plan and there's no question that that's helpful," Rumsfeld said.
He said the U.S. discovery at a deserted al-Qaida camp yielded a large and significant amount of items. Tests were being conducted for traces of chemical, biological and radiological material.
The Tarnak Farms camp, located only a few miles east of the U.S. military's remote desert base about 70 miles from Kandahar, is on a list of more than a dozen locations troops want to investigate, Rumsfeld said.
Army Gen. Tommy Franks said the list of such sites inside Afghanistan has grown to more than 50.
"We are going through them very, very methodically," the general said. Officials were reviewing information about terrorists poisons, explosives, and methods, and taking soil samples.
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