Zahid Al-Sheikh

Zahid Al-Sheikh is the brother to alleged 9/11 mastermind Khalid Sheikh Mohammad. He volunteered to travel to Afghanistan to help fight to resist the Soviet occupation of Afghanistan. Following the ouster of the Soviet forces Zahid is reported to have played a role in planning terrorist projects. He is also reported to have shifted careers to the direction of non-governmental organizations that provided aid to refugees.
Zahid and two of his brothers traveled to Afghanistan in the mid-1980s. His two brothers are believed to have been killed in combat. His youngest brother, Khalid Shaikh Mohammed, who was later to play a senior role in al Qaeda's leadership arrived in 1987. Zahid is reported to have introduced his younger brother to leading anti-Soviet fightger.
According to the 9-11 Commission:

Visiting Pakistan for the first time in early 1987,he traveled to Peshawar,where his brother Zahid introduced him to the famous Afghan mujahid Abdul Rasul Sayyaf, head of the Hizbul-Ittihad El-Islami (Islamic Union Party).

The USA sought Zahid for questioning about whether he played a role in the 1993 World Trade Center bombing.
Zahid is reported to have collaborated with Khalid Sheikh Mohammed in planning Operation Bojinka, a 1995 pland ot hijack 12 airplanes over the Pacific.
American intelligence analysts alleged, during Adel Hassan Hamad's Combatant Status Review Tribunal and Administrative Review Board hearing that Zahid was tied to terrorism and that Hamad's acquaintanceship with him was one of the factors in favor of his continued detention. American intelligence analysts alleged that Zahid was the director of the Jelazee Refugee Camp in Pakistan, and the director of Lajnat Al-Da'wa al Islamia (LDI) in Pakistan. Hamad confirmed that Zahid had been a director of LDI when he first worked as a teacher for the Hira Islamic Institute in the Jelazee Refugee Center, which was supported by LDI, but he told his hearing that Zahid was never the director of the camp.
American intelligence analysts told Hamad's hearing that "other sources" identified Zahid as holding extremist views.
Hamad replied that his relationship with Zahid was a purely administrative one, but he did not believe Zahid was an extremist.