Afghan officials say four Taleban guerrillas were killed when the bomb they were planting on a road went off prematurely.
The incident took place on Saturday night in restive Kandahar province in the south.
Local officials say the insurgents' bodies were blown to pieces.
Taleban fighters have used roadside bombs against U.S. and Afghan government troops, especially in the south and east of the country.
Nearly 60 U.S. soldiers and scores of Afghan troops have been killed in the Taleban insurgency this year, the bloodiest period since 2001 when U.S.-led troops ousted Taleban rulers.
Some information for this report provided by AFP and Reuters.