U.S. jets concentrated on helping Northern Alliance ground troops dislodge Taliban forces Thursday, dropping bombs on the front lines at the major battle fronts near the Afghan capital of Kabul and the key city of Mazar-e-Sharif.

It was the fifth straight day of airstrikes on Taliban forces. About 30 miles north of Kabul, American jets dropped bombs on the Shomali Plain, creating orange bursts of fire and black plumes of smoke. In Samangan province southeast of of Mazar-e-Sharif, Taliban lines were still holding despite 26 separate U.S. raids Thursday, the Afghan Islamic Press agency said, quoting Taliban officials.

In Kandahar, the Taliban's city of origin, U.S. strikes hit a bus near the city gates. At least 10 civilians were killed in a fiery explosion, the Taliban and residents said. The claim could not be independently verified.

Pakistan's largest ambulance service said it was bringing six survivors for treatment in the Pakistani border town of Chaman.

The U.S. strategy appeared to be aimed at helping the opposition consolidate its supply lines, both in the north around Mazar-e-Sharif and in the front close to Kabul.

With Mazar-e-Sharif under control, the anti-Taliban forces would be able to resupply from neighboring Tajikistan and Uzbekistan and would cut Taliban supply lines to Herat and other western areas. Shoring up supply networks is crucial because the approaching winter will cut land routes through the mountain passes on which the Northern Alliance has been forced to rely.

The pattern of attacks on the Shomali Plain suggested that the United States was trying to push the Taliban back from Bagram airport, which is controlled  by the Northern Alliance. Then the alliance could use the airfield to fly in desperately needed supplies and reinforcements for any move on Kabul.

Over Bagram on Thursday, Taliban fighters again fired at U.S. jets. Associated Press Television News footage showed one missile that appeared to pass between two American planes, missing both of them.

During the air bombardment, Northern Alliance fighters on the ground fired rockets onto hilltop Taliban positions. Fighters said they had pulled back about a half-mile from the front line to avoid being caught in the U.S. fire.

Dazzling pyrotechnics notwithstanding, opposition commanders complained anew that U.S. attacks have not been strong enough to dislodge Taliban positions.

"If America wants to finish off terrorism and the Taliban in Afghanistan, they must bring in ground troops," said Eztullah, who was leading a small group of fighters in the town of Korak Dana. "This should be quick."

With U.S. military action against the Taliban intensifying, diplomats stepped up efforts to have a viable post-Taliban government ready if the Islamic regime falls.

On Thursday, Saudi Arabia dispatched its foreign minister, Saud al-Faisal, for talks with Pakistani President Gen. Pervez Musharraf on a possible post-Taliban Afghanistan. Turkish President Ahmet Necdet Sezer arrived in Pakistan for talks on a possible role for Turkish troops in a future peacekeeping operation.

Afghan tribal representatives, meanwhile, ended a two-day meeting in Peshawar, Pakistan, with a call for an end to the bombing campaign and for a multiethnic, broad-based government to replace the Taliban. They also approved a resolution urging the former king Mohammad Zaher Shah to play a role.

In Jabal Saraj, the main spokesman for the Northern Alliance, Abdullah, told reporters the opposition was militarily prepared to move on Kabul, but that it would be better to have a political settlement between "as many Afghan groupings as possible."

He also said that the United Nations would have a key role to play in each of the three phases of a post-Taliban future in Afghanistan: pacification, rehabilitation and reconstruction, and elections.

In other developments:

• Thousands turned out in the southern Pakistan city of Karachi on Thursday for the funeral of an Islamic militant leader killed with 21 comrades when a U.S. bomb destroyed their house in Kabul. Pakistani police filed charges against 150 activists in connection with violent protests surrounding the deaths.

• Secretary of State Colin Powell ruled out a dominant role for Pakistan in shaping the new government, saying the United Nations should take the lead.

• Defense Secretary Donald Rumsfeld acknowledged the United States might not be able to catch Usama bin Laden, but he predicted the Taliban would be toppled. Rumsfeld told USA Today it would be "very difficult" to capture or kill the terror suspect.

• Britain's top military officer, Adm. Sir Michael Boyce, said ground troops will have to stay in Afghanistan for weeks at a time to find bin Laden, The New York Times reported Thursday. Boyce said London is considering sending elite commandos, army paratroopers and Royal Marines trained in mountain and winter warfare.

• Uzbekistan agreed to open its border to allow barges to carry humanitarian aid to Afghanistan, where some 3 million people need food or shelter, Kenzo Oshima, U.N. undersecretary-general for humanitarian affairs, said Thursday.

The United States and Britain launched the military campaign in Afghanistan Oct. 7 after the Taliban refused repeated demands to surrender bin Laden, the chief suspect in last month's terror attacks in the United States.

The Taliban have expelled most foreign journalists from the country, making it difficult for the outside world to examine casualty claims. The United States says bin Laden, his Al Qaeda network, and its Taliban allies are its true targets and insists it is trying to minimize civilian casualties.