In a fertile plain in Kurdish northern Iraq, a black, paved air strip runs between a patchwork of fields dotted by dozens of new, white tents.

The bustle at this remote airfield -- controlled by people without any planes -- has convinced many residents that U.S. forces are preparing to use it for a war against Saddam Hussein.

At the Pentagon on Wednesday, Gen. Richard Myers, chairman of the Joint Chiefs of Staff, was asked whether U.S. ground forces had entered Kurdish areas of northern Iraq.

Myers said he did not want to discuss the disposition of U.S. forces, but then added, "There are not significant numbers of military forces in northern Iraq right now."

Over the past weeks, residents here have reported a sudden increase of movements, such as late-night convoys of trucks and Humvees, a vehicle preferred by the U.S. military.

On Monday afternoon, a Humvee all-terrain vehicle could be seen on a nearby hilltop. Trucks with commercial markings were also moving through the area.

All this has led to speculation that the airport is being readied for use by the Americans for a northern front against Baghdad's forces, which lie less than 60 miles away. The runway at Harir is 8,500 feet -- long enough to accommodate military transports and fighter jets.

Asked about reports of U.S. military cargo planes arriving in northern Iraq recently, Myers said he was not aware of any planes there.

Officials of the Kurdistan Democratic Party, which runs the northwestern section of the autonomous Kurdish zone, denied knowledge of any U.S. military presence and say the Harir airstrip might be used for humanitarian flights.

But a high-level Kurdish official said U.S. specialists were expected to staff airfields in three northern provinces, including Irbil, where Harir is located. He spoke on condition of anonymity.

The privately owned Turkish television station NTV reported Wednesday that if Turkey does not permit American troops to use its bases, the United States plans to airlift troops to the Kurdish areas of northern Iraq. Presumably, airfields such as Harir would fit into such plans.

Saddam's government built the Harir airfield in 1983 and used it to launch airstrikes during the war against Iran. Baghdad abandoned the airfield in 1991 with the establishment of the U.S.-British enforced no-fly zone and the autonomous Kurdish-controlled enclave in northern Iraq.

The base reopened about four months ago.

Abdul Vahid Kheder, a local official of the Kurdish Democratic Party, said reports of new activity were overblown. "It's an international roadway," he said. "Trucks are free to come from Iran, Syria, Turkey. It's no big deal."

But the high-level Kurdish official said 2,000 U.S. military and intelligence specialists are scheduled to enter northern Iraq via the Turkish border to staff and protect the airfields in Dohuk, Irbil and Sulaiymania provinces.

At Harir, military officials would not allow The Associated Press to enter the heavily guarded air base through the main gate. A German camera team attempting to film the site was briefly detained.

But at the air base's ramshackle kitchen -- accessible via a nearby dirt road -- several Kurdish soldiers said they'd been ordered to Harir a few days ago in preparation for a possible U.S. arrival.

Kurdish officials briefly closed the main road passing by the airstrip Monday, as they have reportedly done several times over the last few months. Desert-camouflage vehicles and soldiers in tents guarded access roads.

"Everyone is waiting for the Americans to come," says Abdul Samad Ismail, a customer at the Shirwan restaurant in Harir. "We know they're coming."

Officials in the Kurdish enclave have long told of occasional visits by American military personnel planners, mostly to survey airfields. According to Kurdish authorities in Sulaiymania, U.S. Special Forces visited the area several months ago.

The U.S. presence was far greater from 1991 to 1996, Kurdish officials say, when both the State Department and Pentagon had offices here as part of Operation Provide Comfort, in which some 5,000 American troops were deployed.

They left, however, during the civil war between rival Kurdish factions.

Some Kurdish Democratic Party officials said the reopening might be unrelated to any U.S. plans.

"It is the most realistic method of providing humanitarian assistance in a very urgent situation," Fawzi Hariri, a high-level KDP official said Tuesday. "We hope that the U.N. and aid agencies will take advantage of it."

But a Kurdish military official, who spoke on condition of anonymity, insisted that the Kurds reopened the base to "secure the runway themselves to prevent unauthorized foreign aircraft from landing."

The different accounts of why the airfield has been reopened may stem from political sensitivities. Iraqi Kurds recently have been trying to placate neighboring countries such as Iran, Turkey and Syria, which have Kurdish minorities of their own and which are hostile to the self-rule experiment lest it encourage unrest in their countries.

The reopening of the air base at Harir -- less than 100 miles from the Iranian border -- and other signs of military activity in the Kurdish region have already caused concern in Iran, whose state-controlled Arabic-language satellite television reports such operations with alarm.

Iran, which President Bush designated a member of an "axis of evil," fears its territory could become the target of an American military assault following a possible attack on Iraq.