A remote control bomb that witnesses said was set off by two unknown men on a nearby hilltop ripped through an Afghan provincial governor's vehicle on Saturday, killing the governor and three others, officials said.

The blast killed Abdullah Wardak, the governor of Logar province, two of his bodyguards and a driver, said Gen. Zalmay Khan, a police commander in Kabul province.

The explosion occurred only about 500 yards from the governor's home. He had been traveling in the second car of a three-car convoy that was headed for parliament. The bomb detonated directly on the governor's vehicle, shredding the front half of the SUV and flipping the remains upside down.

Taliban spokesman Zabiullah Mujahid claimed responsibility for the attack.

A resident in Paghman, the area where the attack occurred about 12 miles west of Kabul, said he saw two men on the side of a hill near the road where the explosion detonated. Mohammad Shoaib said that after the bomb went off, the two men ran away. Authorities found wires on top of the hill, he said.

Wardak, a former Cabinet member, was in charge of Logar, the province directly south of Kabul. Afghanistan has 34 provinces, each headed by a provincial governor.

Militants frequently target government leaders in their campaign of violence against Afghan authorities.

Meanwhile, NATO's International Security Assistance Force said one of its soldiers was killed Friday when insurgents fired on a patrol. No other details were released.

More than 4,100 people have died in insurgency related violence this year, according to an Associated Press count based on figures from Afghan and Western officials.