Abdullah Mehsud, who spent 25 months in custody at the US base in Guantanamo Bay, died in south-western Balochistan province, a police spokesman said.
“Abdullah Mehsud blew himself up with a grenade and died when security forces raided his hideout. Three of his accomplices were arrested,” he said.
Released from Guantanamo in 2004, he quickly resumed his militant role and was involved in the kidnap of two Chinese workers, one of whom died during a rescue bid by Pakistani forces in South Waziristan later that year.
Analysts say the kidnapping was an attempt to secure the release of al-Qaeda militants held during Pakistani army operations in South Waziristan.