KABUL, Afghanistan -- The United States raised the specter of renewed foreign meddling in Afghanistan on Friday and said Iran may be sending pro-Iranian Afghan fighters to destabilize the newly installed U.S.-backed government.
U.S. special envoy Zalmay Khalilzad stopped short of directly accusing Iran of interference but cited unspecified reports that Afghan fighters and money were being sent from Iran into the extremely volatile country to build opposition to Prime Minister Hamid Karzai.
"All of those things would be regarded as interference," Khalilzad said.
Earlier this month, President Bush warned Iran against harboring al-Qaida fighters and trying to destabilize Afghanistan's new government.
The Iranian Foreign Ministry spokesman rejected Bush's remarks as "baseless."
Army Gen. Tommy Franks, commander of the U.S. war effort in Afghanistan, echoed Khalilzad's comments during a briefing at U.S. Central Command headquarters in Tampa, Fla.
"There has been a perception among several of the leaders inside Afghanistan that Iran has in some cases not been terribly helpful," Franks told reporters.
Franks said U.S. forces continued working against pockets of Taliban and al-Qaida resistance, about 10 of them at any given time.
"We have found tanks, we have found armored personnel carriers. We have found thousands and thousands of rounds of ammunition.
"We have found artillery ammunition, we have found mortar ammunition, we have found small arms, we have found rocket-propelled grenades, and we have found...filing cabinets full of documentary evidence," he said.
Despite their common Islamic faith, Iran fiercely opposed the former Taliban leadership. Since the Taliban collapsed last month, Iran, Pakistan, India and other countries in the region have been competing for influence among the various Afghan factions.
Tribal rivalries, with some factions backed by Iran, tore the country apart after the Soviet Union ended its occupation in 1989. The civil war opened the way for the Taliban to take control of the fractured country in 1996.
In an effort to broaden his support, the interim prime minister flew to Saudi Arabia on Friday for his first trip abroad since taking office Dec. 22. Afghan officials said Karzai would meet with Saudi officials and make a religious pilgrimage to the Islamic holy city of Mecca. He will then travel to Japan for a conference of potential international donors this week.
Rep. Jim Kolbe, an Arizona Republican who visited Afghanistan last week, said the country needs at least $8 billion over the next 10 years.
"It's up to Congress to decide, but I think the United States can provide between 10 to 15 percent of that," Kolbe, a member of the House appropriations committee, told reporters in Rome.
In other developments:
-- Pakistani President Pervez Musharraf told CNN that he believes Osama bin Laden may have died because he couldn't get treatment for a kidney ailment. U.S. officials said they have no evidence bin Laden suffered from severe kidney problems or had died.
-- An American man who reported being kidnapped by a tribal warlord during a private relief mission in Afghanistan has been released, a family friend said in Harvest, Alabama. Karen Allen, who has been a spokeswoman for the family of Clark Bowers, said she was not clear where Bowers was or whether a $25,000 ransom had been paid.
-- Bosnian authorities turned over to U.S. military authorities six Algerians suspected of having links to international terrorism. A U.S. official in Europe said the six would be taken to the U.S. naval base at Guantanamo Bay, Cuba.
More than 20 years of warfare have left Afghanistan destitute, and since the collapse of the Taliban international organizations have been rushing humanitarian aid to the country to prevent famine and begin the long process of rebuilding.
On Friday, the World Food Program announced it had begun delivering food by donkey to remote mountain regions of northern Afghanistan, where bad roads and snow have isolated thousands of people in the country's so-called hunger belt.
"There's only so many donkeys, so there's only so many donkeys we can hire to deliver food," Catherine Bertini, executive director of the WFP, said in an interview in Rome.
Last week, the agency started delivering food in Bonavash, a village where people were eating bread made of grass and feeding infants grass porridge. Bonavash lies in a mountain region about 90 miles southeast of Mazar-e-Sharif.
In the southern city of Kandahar, the spiritual heartland of the Taliban, U.N. aid agencies have started to reopen their wrecked and looted offices and bring back international staffers.
Maki Shinohara, a spokeswoman for the U.N. High Commissioner for Refugees, said three international staffers were largely confined to the office or their guest house because of security concerns, which she described as "extremely fragile."
The largest concentration of U.S. forces in Afghanistan is at a base Kandahar International Airport. The Marines who established the base were handing over control Friday to the Army's 101st Airborne Division.
The base came under fire Jan. 10 during the first flight of al-Qaida and Taliban prisoners from a temporary detention center there to the Guantanamo Bay Naval Station on Cuba.
In recent days, Marines found munitions and tunnels outside the perimeter of their base and believed they were being targeted for another attack.
"This remains a very, very dangerous place," said Maj. Ignacio Perez, a spokesman for the 101st.
A planeload of 30 Taliban and al-Qaida prisoners was flown from the base to Pakistan late Thursday. Military spokesmen declined to comment on the flight, but the detainees were presumed to be Pakistani nationals.
In the past week, 110 prisoners from the Kandahar base have been flown to Guantanamo, and human rights groups have said strict security measures -- including chain-link cells that have been likened to cages -- violate the prisoners' rights. The United States denies the charges.
The International Committee of the Red Cross is interviewing some of the prisoners at Guantanamo and assessing of conditions at the camp.
Franks said each of the prisoners would be interviewed by U.S. authorities to determine their "intelligence value."
"We have done that in Afghanistan to an extent. When we have them in Guantanamo Bay, that sort of interrogation will continue, and then determinations will be made as to whether a given detainee may be retained for intelligence value or may be handed over for prosecution within legal channels," Franks told reporters.
The general said the legal procedures for dealing with the captives after interrogation were still being worked out in Washington.