Attackers set off a remote-controlled bomb near a vehicle carrying U.S. special forces along Afghanistan's eastern border with Pakistan, but no casualties were reported, a U.S. military spokesman said Wednesday.

The device went off as the troops were conducting a reconnaissance patrol at a border checkpoint near the eastern town of Khost, Col. Rodney Davis, the U.S. military spokesman, said in a statement from Bagram Air Base (search).

"The device was detonated by remote control. There were no injuries and only a cracked windshield and headlamp to the vehicle," Davis said.

Last week, a U.S. special forces soldier was lightly wounded in an explosion that appeared to be caused by a homemade bomb near Gardez, northwest of Khost. It also detonated near a U.S. military vehicle, and shrapnel struck a soldier's neck but did not seriously injure him.

About 11,500 coalition troops, the majority of them American, are in Afghanistan carrying out operations in search of Taliban (search) rebels and their allies. The Taliban were overthrown in a U.S.-led war in 2001.

Coalition troops regularly seize weapons caches found in caves or hidden in villages. The weapons are usually destroyed or handed over to government authorities.

Davis said U.S. special forces had recovered a cache of up to 800 anti-tank and anti-personnel mines from a compound near Gardez. The mines will be destroyed.

Around 200,000 people have been injured by mines and unexploded ordnance in Afghanistan (search) over the last two decades of war, according to the International Red Cross. The country is one of the most heavily mined nations on earth.