In another sign of the rapidly escalating turf war between two of the world's leading Islamist militant organizations, the Afghan Taliban has warned Islamic State (IS) militants against extending their operations to Afghanistan.
In an open letter to IS leader Abu Bakr al-Baghdadi dated June 16, Taliban leadership council head Mullah Akhtar Muhammad Mansour wrote that "the creation of a parallel jihadist front or leadership [in Afghanistan] will pave the way for disagreements, schisms, and conspiracies."
The letter follows defections and reports of escalating clashes between fighters loyal to the two militant organizations.
While refraining from the fiery rhetoric typical of Taliban writing about the United States, its NATO allies, and the Western-backed Afghan government, Mansour instead delivers a stern warning to al-Baghdadi.
"[We] will be forced to react to defend our achievements," the letter said. "In the light of religious sanctions, you should help your brothers in the Islamic Emirate [Taliban] to remain united and strong and refrain from taking steps from afar that result in disappointing the mujahedeen [Taliban] leaders, religious scholars, and thousands of pious fighters, which will prompt them to lose their love and sincerity for you."
The letter is the most open and detailed acknowledgement of the threat the emergence of IS has posed to the Afghan Taliban, who have largely preserved their unity despite being toppled from power nearly 14 years ago.
In one of the most revealing passages in the letter, Mansour warns al-Baghdadi against trusting the judgment of people "who were either disappointed with the Taliban because of various reasons or thrown out of their organization for committing crimes."
Afghan sources familiar with the Taliban say that the mention of former Taliban members is a subtle reference to Mullah Abdul Qayum Zakir. The former top Taliban commander was sacked by Mansour in April 2014.
Since then, the two have emerged as major rivals. Meanwhile, Mansour has tightened his grip over the Taliban leadership council in exile in Pakistan by appointing himself the acting leader of the council, which is often referred to as the Quetta Shura after the southwestern Pakistani city from where it allegedly operates. He has also appointed loyalists from among his Ishaqzai tribe to the council. They often make appointments and decisions in the name of fugitive Taliban leader Mullah Mohammad Omar.
Zakir, on the other hand, has generally kept a low profile, but late last year he reportedly traveled to Iran to explore the possibility of establishing a Taliban sanctuary there.
Sources familiar with this emerging power struggle within the Afghan Taliban say Mansour and his leadership council are now worried over Zakir possibly becoming the new IS leader in Afghanistan.
A prisoner with Zakir in the U.S. detention center in Guantanamo Bay, Cuba, Mullah Abdul Rauf Khadim became the first Taliban leader to openly defect to IS. In January this year, purported IS spokesman Abu Muhammad Al Adnani said that Khadim was appointed as the deputy head of Khorasan, a region comprising all of modern day Pakistan and Afghanistan and surrounding countries.
Khadim was killed in an airstrike in the southern Afghan province of Helmand in February. According to Agence France-Presse, his successor Hafiz Waheed was also killed in March.
During their detention in Guantanamo, Khadim and Zakir are thought to have converted to Takfiri Salafism, a hardline offshoot of Salafism, which is the state religion of Saudi Arabia and many neighboring Gulf states.
While IS and Al-Qaeda follow Takfiri-Salafism, the Taliban leaders and cadres adhere to Deobandism, a puritanical from of Hanafi Sunni Islam practiced in South Asia.
In his letter Mansour also made subtle references to such religious differences, and urged al-Baghdadi to follow in the foot steps of Arab Salafi militant leaders Abdullah Azam and Osama Bin Laden, who either pledged an oath of loyalty to the Taliban or refrained from converting Afghan militants to Takfiri-Salafism.
"Because of its sacrifices and thoughtful politics, the [Taliban] Islamic Emirate has earned massive popularity," Mansour claimed. "If the people here who claim to be associated with you create mischief here, it will make Muslims all over the world upset with you."
IS militants now control large swathes of territory in Syria and Iraq. It is now considered one of the richest terrorist organization and has been trying to establish a foothold in South Asia where the modern jihadist movement was born during the Soviet occupation of Afghanistan in the 1980s.
In the December issue of its official magazine Dabiq, IS militants reportedly criticized the Afghan Taliban for being incapable of controlling and conquering territory, failing to target the Shi'a Muslims, and for recognizing international borders. The article also criticized the Taliban leader Mullah Mohammad Omar for "practicing and preaching a bankrupt, distorted version of Islam."
The emergence of IS has already pushed the Afghan Taliban to explore cooperation with its historic nemesis, Iran. Mansur's emissaries reportedly discussed the IS thereat with Iran's powerful Islamic Revolutionary Gaurd Corps in May.
In a sign of expected escalation between the Taliban and IS, Mansour warned that his followers will be forced to react to preserve their achievements.
"Any mobilization and activities under different flags is detrimental to Jihad, Islam, and Muslims," he wrote.