Updated

U.S. Marines strengthened their grip on a new airbase outside Kandahar Tuesday, one day after fighter jets attacked approximately 15 armored vehicles "in the vicinity of" the staging ground.

Two F-14 Tomcats hit the armored column on Monday, said Maj. Brad Lowell, a spokesman for the U.S. Central Command in Washington. He said Marine AH-1W Cobra helicopters were in the area but did not fire on the armored vehicles.

Earlier Marine spokesman Capt. David Romley said Cobras had attacked 15 tanks and armored personnel carriers and destroyed some of them.

There was no word on casualties for either side.

Romley did not say who manned the vehicles, but the desert airstrip the Marines seized Sunday night is in the region of Kandahar, the last major stronghold held by the Taliban.

Romley would not say if the armored column was heading toward the base or give any details about where it was attacked, except to say it was "in the vicinity of this base." He said the vehicles had been spotted by U.S. aircraft.

Romley said the column included tanks and BMPs, which are armored vehicles capable of carrying a dozen soldiers each.

Meanwhile, helicopters and transport planes ferried troops and equipment into the new Marine base late into the night, and the Pentagon said it would take at least another day to reach the full complement of about 1,000 Marines. The aircraft were operating off the USS Peleliu hundreds of miles away in the northern Arabian Sea and from unidentified bases on the coast.

Working under a bright moon in the chill night air, Marines hurried to set up shop and fortify the airstrip for a new phase of the U.S. war on terrorism. Until now, the U.S. role in the war had been mostly in the air.

Carried by CH-53E Super Stallion heavy lift helicopters, the first contingent of Marines touched down at the desolate airstrip at 9 p.m. local time Sunday and met no resistance, according to their reports.

"The Marines have landed and we now own a piece of Afghanistan," Gen. James Mattis, commander of the task force, said Monday. "Everything went without a hitch."

In Washington, Defense Secretary Donald H. Rumsfeld declined to talk about what kinds of operations might be staged from the base. He suggested only that it would ratchet up the pressure on the leaders of the Taliban and Usama bin Laden's Al Qaeda network by further hindering their movements in the Kandahar area.

Rumsfeld also said that "hundreds, not thousands" of Marines would man the "forward operating base," but not necessarily as the vanguard of a substantially larger American ground force.

Earlier, President Bush said the Marines would assist in hunting down terrorists linked to the Sept. 11 attacks on the World Trade Center and the Pentagon.

The base is isolated, with no signs of towns in the distance across the flat desert. The only lights for miles around were the runway lights installed by the Marines and lights burning inside the airstrip's buildings.

Col. Peter Miller, chief of staff of the Marine task force, said the sand landing strip and buildings had been built by a wealthy Arab to provide access to his hunting lodge. The compound includes a small mosque with a minaret and a large white building that may have served as a hangar.

There are more than 4,000 Marines in the two units contributing troops to the operation: the 15th Marine Expeditionary Unit from Camp Pendleton, Calif., and the 26th from Camp Lejeune, N.C., which are on amphibious ships in the Arabian Sea. The units are trained for ground combat, evacuations, humanitarian aid and other missions.

The first troops to land — from the 15th brought in by helicopters — were watched over by AH-1W Cobra and UN-1N Huey helicopter gunships, Harrier jump-jet fighter-bombers and other aircraft.

The aircraft flew as far as 400 miles from their ships in what was described as the longest amphibious and air deployment ever conducted by the Marine Corps.

"We are going to operate at the very extremes of the ability of our machinery," said Miller, the task force's British-born chief of staff. "We would much prefer to be closer in, because it just makes it logistically that much easier for us. But the way this operation is designed, with the intermediate staging bases, we'll be able to pull this off."

Shortly before the operation began Sunday night, the steel hull of the Peleliu echoed with the sound of gunfire as infantrymen tested their weapons by firing into the sea from a wide doorway. Then they hauled their packs, weapons and protective gear — often pushing 100 pounds of equipment — to transport helicopters waiting on deck.

As some of the Marines boarded the helicopters, beads of sweat on their faces from the heat and the strain of carrying their heavy gear, a Navy chaplain, Lt. Cmdr. Donald Troast of Boston, touched some on the shoulder.

Once they had boarded, he stood with his head bowed. He said later: "I asked God to bless every one of them. I don't care what their religion is."

The Associated Press contributed to this report