WASHINGTON/ISLAMABAD, 30 October — American warplanes yesterday targeted caves and bunkers used by Osama Bin Laden’s force of radicals as the United States sought to shake off the impression that its four-week-old campaign was floundering. As the Pentagon announced raids on underground hide-outs in the east of Afghanistan, the commander in chief of the military action was in Pakistan seeking to reassure its nervous top brass.

But Afghanistan’s ruling Taleban militia, which is sheltering Bin Laden, mocked the US offensive as ineffectual and claimed to have arrested an unspecified number of Americans within the country. "In the first phase (of the war) there is no significant achievement as the Pentagon wished to achieve, except the genocide of Afghan civilians," the Taleban’s Ambassador to Pakistan, Abdul Salam Zaeef, told a press conference in Islamabad.

The relentless airstrikes entered their fourth week with no end in sight, no sign that the Taleban’s grip on power was weakening and no reports that the anti-Taleban opposition forces had yet gained any ground. The campaign has cranked up tensions in Pakistan, Washington’s key front-line ally in its bid to avenge the Sept. 11 attacks that killed at least 5,000 people in the United States, provoking a spate of violence.

Gen. Tommy Franks, head of US Central Command, arrived in Islamabad after Defense Secretary Donald Rumsfeld was forced to deny US forces were entering a "quagmire" with rising civilian deaths and few visible successes. US and British officials were also forced to defend the strikes against growing reports of mounting civilian casualties and an imminent humanitarian disaster as thousands of refugees flee ruined Afghan cities.

Franks held talks with Pakistani President Pervez Musharraf and his senior commanders, officials said. Pakistan’s support for the US campaign has provoked growing anger in a country where many have ethnic ties with Afghans and some share their radical vision of Islam.

Musharraf said at the weekend that he hoped the US strikes would be over quickly and that they should stop before the holy month of Ramadan begins in the middle of next month. But Washington’s ambassador to India, Robert Blackwill, said yesterday that this was unlikely to happen. "It is ... felt that if the attacks are reduced during Ramadan, it will provide an opportunity to the Taleban to boost their military strength," he told a news conference in Bombay.

Rumsfeld accused the ruling Afghan militia of lying about the civilian toll and of using mosques and schools as ammunition dumps and command centers.

The UN envoy to Afghanistan, Lakhdar Ibrahimi, was in Pakistan and scheduled to meet Foreign Minister Abdul Sattar for talks on post-Taleban political options for Afghanistan, foreign ministry officials said. Ibrahimi, who arrived on Sunday, was expected to meet Musharraf today, they said.

The Taleban mocked the US war effort and claimed to have captured a number of Americans. "The only significant achievement these intensified air raids brought the Americans is a wave of anti-American campaigns throughout the world," Zaeef told reporters. "There have been arrests," Zaeef said when asked if any Americans had been arrested, "I don’t know how many there are or where they are or what their condition is."

The Taleban are known to be holding a number of foreign nationals — including a French, a Japanese and two Pakistani journalists arrested since the strikes began — and have warned that they could face trial for spying.

Apparently frustrated by the slow pace of developments on the ground and the mounting civilian death toll from so-called collateral damage, the Pentagon acknowledged it was considering the establishment of a base inside opposition-held Afghan territory, from which it could better prosecute its war. "Sure, that (a base) is one of the things were are looking at," a senior defense official told Reuters. The proposed forward base would support opposition Northern Alliance forces fighting to overthrow the Taleban from their base in the Panjshir Valley.

The official gave no details but a report in the USA Today newspaper said the base could be manned by up to 600 soldiers, providing security, food, medical care and evacuation support to 200 to 300 Special Forces commandos.

Pentagon spokeswoman Victoria Clarke declined to confirm or deny plans for a forward base — something military analysts have said was only a matter of time — but she made it clear the latest airstrikes had targeted men and materiel from the Taleban and Bin Laden’s Al-Qaeda network. The armed anti-Taleban opposition, a loose coalition fighting under the banner of the Northern Alliance, also warned that the US attack was a long way from toppling the Taleban. "The perception might have been that the Americans started bombing and we will be in Kabul and Kandahar. This is not the way things will happen," Northern Alliance foreign minister Abdullah Abdullah said.

"There are two messages: the United States has to be patient, and things could have been done better and can be done better," he told reporters at a news conference in the opposition held town of Jabal Seraj. Three top leaders from the Northern Alliance met to agree to mount an assault on the key northern city of Mazar-e-Sharif.

The assault will be supported by US airstrikes and a small number of US special forces military advisers. Uzbek warlord Abdul Rashid Dostum and fellow Northern Alliance commanders Muhammad Atta and Haji Muhammad Muhaqiq met Sunday in the Dara-e-Souf valley and "approved a new war plan," a spokesman for Atta told reporters. "A new offensive will begin within the next two or three days," he said.

The assault will be supported by US airstrikes and a small number of US special forces military advisers. Uzbek warlord Abdul Rashid Dostum and fellow Northern Alliance commanders Muhammad Atta and Haji Muhammad Muhaqiq met Sunday in the Dara-e-Souf valley and "approved a new war plan," a spokesman for Atta told reporters. "A new offensive will begin within the next two or three days," he said.

Taleban forces have so far repulsed a series of offensives aimed at capturing the strategic town with support from US airstrikes. The decision to mount a new assault on Mazar-e-Sharif came after US warplanes opened a new front Sunday, bombing for the first time Taleban positions in northeast Afghanistan close to the Tajik border. But Abdullah said the bombing would have to be stepped up. "Round-the-clock bombing is needed. Intense bombing, carpet bombing," he said, adding that while the past week of occasional strikes on Taleban positions had largely hit their targets, they were not enough.

Taleban also accused the United States yesterday of using chemical weapons and invited foreign observers to check the claim. But one deputy minister acknowledged that the war-shattered country did not have the facilities to test for chemical use. "We have some patients with superficial injuries with symptoms of chemical weapons," doctor Wazir of Kabul’s Wazir Akbar Khan hospital, told a news conference.

Public Health Minister Mullah Abbas also said the militia had proof that chemical weapons were being used. "Our findings prove that this is true. These bombardments have radioactive rays and chemical materials that also cause cancer," he told the same news conference.

In addition to the political and social fallout from the war next door, a clue to the extent of Pakistan’s economic woes emerged yesterday when the central bank cut its economic growth forecast for 2001-2002 from four to 2.5 percent.

In a display of unity with the Taleban, several thousand heavily armed Pakistani Pashtun tribesmen had massed near the Afghan border ready to cross and join the regime to fight off the Americans. Zaeef said that the Taleban had advised them not to cross because the group would provide an easy target to US bombings. In the southern city of Quetta however, which has been the scene of large scale violent anti-American demonstrations in the past, a rally called in support of the Taleban attracted only 4,000 people.

Arrest of Saudi denied

In Islamabad, Saudi Ambassador Ali Aseery denied reports that a Saudi and his Afghan companion were arrested while leaving Afghanistan. Police said in Peshawar said the two men were arrested for investigation of possible links to Al-Qaeda.

Musa ibn Mazhan ibn Salman Al-Saifi was carrying no passport or other travel documents when he was detained Sunday at the Torkham crossing point, police said. His Afghan companion, known only as Sangeen, was also detained, they added. But Ambassador Aseery told Asharq Al-Awsat by telephone that the Pakistan government had not confirmed the arrest.