Khalid Balti, also known by the nom de guerre Muhammad Khorasani when he served as the spokesperson of the group, was killed in Nangarhar province, a security source told Al Jazeera on Tuesday.
The official spoke on condition of anonymity because he was not authorised to speak to the media on the issue.
“It is clear that the person who was killed is Khalid Balti,” added the official, while also confirming the killing took place in Afghanistan’s Nangarhar province, along the border with Pakistan.
When asked about the circumstances of the killing, he stated, “We are trying to get that information.”
Local media in Pakistan reported that Balti had been shot dead by unidentified gunmen, but the source was unable to confirm those reports.
In a statement, the Pakistani Taliban, announced that “investigations were ongoing” into the reports that Balti had been killed.
“It should be remembered that Mufti Khalid Balti did not currently have any responsibilities in [the Pakistan Taliban],” the statement added.
Balti’s alias of Muhammad Khorasani became a moniker for each successive Pakistan Taliban spokesperson, and the group clarified that the current spokesperson was “alive and well”.
Balti, said to be in his late 40s, hailed from the northern Pakistani region of Gilgit-Baltistan, and took over as Pakistan Taliban spokesperson from Sheikh Maqbool – who went by the alias Shahidullah Shahid – in 2014.
That year, the Pakistani military launched a security operation against the Pakistan Taliban in its erstwhile headquarters and stronghold of North Waziristan, displacing the group and many of its fighters into eastern Afghanistan.
The Pakistani security source described Balti as a “pivotal leader” of the Pakistan Taliban, contradicting the armed group’s claims.
It is unclear what, if any, operational role Balti has played with the Pakistan Taliban recently, after being released from Afghan government custody by the Afghan Taliban when that group took control of Kabul in August.
Last month, a month-long ceasefire between the Pakistani military and the Pakistan Taliban ended without renewal, as a nascent peace process – brokered by the Afghan Taliban – appeared to have stalled.
The Pakistan Taliban claimed the Pakistani government had reneged on its promises to release Pakistani Taliban prisoners and to cease security raids on TTP hideouts.
