Police say four people have been killed in an explosion targeting Afghanistan's energy minister outside a school in the country's west. A Taliban official is claiming responsibility. Police spokesman Raouf Ahmadi says Energy Minister Ismail Khan and his delegation escaped unharmed after Sunday's bombing on the main road to the airport in Herat, but the blast killed four civilians and wounded 17 people. Khan is considered the major powerbroker in the region and was once governor of Herat, a western province bordering Iran. A Taliban spokesman, Zabiullah Mujahid, claimed responsibility for what he said was a car bomb targeting Khan. He said Khan was among the dead, though Mujahid's claims often turn out to be false.