ISLAMABAD, Pakistan—The family of a taxi driver who was killed alongside Taliban leader Mullah Akhtar Mansour in a U.S. drone strike has registered a case with Pakistani police against unnamed American officials over the attack.

Mullah Mansour was killed on May 21 in Pakistan’s southwestern Balochistan province after he entered the country from Iran. Pakistani officials and family members said he hired the vehicle in the Pakistani border town of Taftan, and driver Muhammad Azam had no links to any militant group.

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