Khalid Mehsood, deputy leader of the umbrella Tehreek-e-Taliban Pakistan (TTP), died after the pre-dawn strike in North Waziristan tribal agency on February 8, the militants said in the emailed statement.
Pakistani intelligence officials say a USA drone strike has hit a militant compound in a northwestern tribal region near the Afghan border, killing seven militants from the Taliban-affiliated Haqqani network.
The slain commander was also believed to be closely linked to the Haqqani network blamed for staging high-profile terrorist attacks against local and USA -led forces in Afghanistan.
Washington has designated Sajna a global terrorist.
Several of his aides were also killed in the attack. He added that a commander called Mufti Noor Wali Wali was appointed by the Taliban chief to succeed Sanja.
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The figures from the two Koreas shared kimchi (Korean pickled cabbage) and soju rice liquor, and spoke for three hours. She is the first member of the Kim family to visit the South since the Korean War.
Pakistani security officials insist that majority of the Taliban leaders and fighters have fled to neighboring Afghanistan after the military carried out major offensive in the tribal regions.
The TTP has been blamed for many suicide bombings and other attacks.
Omar Zawak, the provincial government spokesman, confirmed the incident saying the Taliban also assaulted the NDS Center while the insider attack was under way, sparking fierce clashes with Afghan security guards.
Pakistani authorities suspect Sajna played a role in planning major terrorist attacks in the country and was instrumental in a jailbreak in 2012 in the northwestern town of Bannu that freed about 400 inmates, including militants.
Lying south to the Taliban's birthplace Kandahar, Helmand remains one of the most volatile provinces in Afghanistan with militants controlling large swaths of land.