A former Guantánamo detainee, he is believed now to be a deputy to reclusive Taliban leader Mullah Omar, a position he assumed upon Pakistan's arrest of the movement's former No. 2, Mullah Abdul Ghani Baradar, and a number of other Taliban leaders.
Pakistani intelligence agents arrested Zakir and a close associate earlier this year in early February, according to Western and Afghan government sources, but both were later released without explanation.
Raised in prosperity
Hailing from a well-off Pashtun family with roots in southern Helmand Province, Zakir grew up in the northern province of Jowzjan. His associates say he is in his early 40s, making him too young to have joined the anti-Soviet resistance of the 1970s and '80s as his older brother had done.
Instead, like many boys at the time, he was sent to study in madrasas, or religious schools, near the Afghan-Pakistani border that taught an extreme version of Islam. He attended such a school in Quetta, Pakistan, then a hotbed for radicalism. There he met an influential figure who would later become a major Taliban commander and his partner in arms, Mullah Abdul Raouf.
By 1997, the pair had returned to Afghanistan and joined the Taliban, the movement of religious students who had swept into power on a platform of law and order and a puritanical, often violent interpretation of Islam.