A US statement on Sunday says helicopters carried the troops into the Shah Wali Kot district of Kandahar province, where they clashed with the militants.

It says the clash on Saturday killed 17 insurgents, while no US or Afghan troops died.

Southern Afghanistan is the center of the Taliban-led insurgency.

More than 5,200 people - mostly militants - have died in insurgency-related violence this year, according to an AP count. -- AP