One U.S. Marine lost his foot and two others were injured in Afghanistan after a land mine exploded at the airport in Kandahar.

Cpl. Chris Chandler was evacuated from Afghanistan and flown to a hospital in unidentified country after the explosion Sunday, said Capt. David Romley, a Marines spokesman.

The two other Marines, Sgt. Adrian Aranda and Lance Cpl. Nicholas Sovereign, suffered wounds in the arms and hands but were in stable condition at the Marines' Camp Rhino southwest of Kandahar.

The three Marines were helping to clear the airport of anti-personnel mines when Chandler stepped on a plastic mine that had eluded a sweep by detectors searching for metal mines.

Romley said Monday they were part of an advance infantry party safeguarding the explosives-clearing teams behind them.

They were moving into an area that was outside the original perimeter Marines set up when they seized the abandoned airport on Friday.

Meanwhile, 13 loads of troops and materials were flown into the airport aboard C-130 transport planes during the night despite unusually heavy rains for this parched region of southern Afghanistan, said Lt. James Jarvis.

Jarvis said the Marines had arrived to expand their security lines around the airport to the south and east. Local anti-Taliban forces were also helping to provide a security ring around the airport.

Under an early morning rainbow, Marines set up tents and equipment in the derelict airport, which had been stripped of its inventory since it was last used two years ago for commercial flights.

In front of the arched facade of the main airport terminal, Marines erected a huge tent under camouflage netting in less than an hour.

Navy Seabees and other construction units were preparing to repair runways bombed to asphalt pieces during the two-month U.S. air campaign against Kandahar, the base of Afghanistan's former Taliban rulers.

Jarvis said about one-third of the 10,000 feet of runways and taxiways were usable. Other areas remained blocked by debris or were deemed unsafe.

Jarvis said Marines remained on alert even though the airfield has been peaceful since it was seized by the U.S. troops.

"There is still a terrorism threat out there," he said. "But we hear that citizens have largely been friendly to U.S. forces."

Four U.S. military personnel have died in Afghanistan since the war began Oct. 7. Three Army Green Berets were killed by a misdirected U.S. bomb near Kandahar, and a CIA agent died in a prison uprising in the northern town of Mazar-e-Sharif.

The Associated Press contributed to this report.