The pressure on the Taliban and al-Qaeda forces in Afghanistan is mounting, as U.S. warplanes attacked several cave and tunnel complexes around the cities of Jalalabad and Kandahar, according to Pentagon sources.

The Defense department also denied reports that 160 prisoners were executed by the Northern Alliance.

“The reports are just not believable. A U.S. liaison team is on the ground with opposition forces in the area,” said Victoria Clarke, assistant secretary of Defense. “The team has not reported the capture of more than a handful of prisoners.

“Additionally, the team has not reported any information about improper treatment of prisoners, and would certainly do so, if they had witnessed that or learned of these sorts of deaths,” Clarke added.

Defense officials also confirmed that the military is trying to establish a northern airbase, although they suggest that it would be used primarily for humanitarian purposes, which are “continuing.”

“Two C-17s [dropped] about 34,000 humanitarian daily rations,” said Rear Admiral John Stufflebeam, of the Joint Staff. “That brings our total now to date to more than 1,970,000.”

Stufflebeam described Wednesday’s air strikes, which targeted eight areas.

“We’re continuing to focus the pressure on al-Qaeda and the Taliban through strikes on fixed and emerging targets,” Stufflebeam said. “Most of our effort was against emergent targets, including Taliban command-and-control facilities and military forces in the South and in support of opposition group efforts there.

“We used about 120 strike aircraft again yesterday, which includes about 100 tactical sea-based platform aircraft, 12 to 14 land-based tactical jets, and between six to eight long-range bombers,” Stufflebeam added.

Secretary of Defense Donald Rumsfeld told reporters on Tuesday that the Marine deployment was going as planned.

“My understanding is that the deployment is going along very well and it’s continuing. They’re there to establish and secure a temporary forward operating base,” Rumsfeld said. “Is it conceivable that some day some one of that group could be used for some other purpose? The answer is: it’s conceivable. Is it intended at the present time? No.”

The Pentagon declined to confirm reports that the Northern Alliance had invaded the southern city of Kandahar, although the troops may be in the province.

“We can’t deny that, I guess, is a better way to put that,” Stufflebeam said. “But I could not confirm, and I’ve not seen any reports that any opposition groups have entered Kandahar City at this point.”

Stufflebeam did confirm that the city itself was surrounded, but would not say it was under siege.

“The city of Kandahar is in a large way relatively surrounded by opposition groups. The major road that goes to the south towards Quetta is controlled by opposition groups,” Stufflebeam explained. “So the city is somewhat ringed by opposition groups.”

The situation in Kandahar is complex, and negotiations between the opposition forces and Kandahar’s defenders are on going.

“They’re very active in negotiations from those who are within the city and those who are outlying,” Stufflebeam said. “We know there are Taliban forces that are digging in, intending to fight, would be my assumption. We know there are non-Taliban forces there as well, who have already broadcast their intentions to dig in and fight to the death.

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