 After fleeing China in 1997 to Mecca, Mahsum joined the Taliban and lived in Afghanistan and Pakistan; he held an Afghan passport issued by the Taliban.In early 1999, he was said to have met with Osama bin Laden, who offered him US$300,000 of financial assistance for the East Turkestan Islamic Movement in the following year; Mahsum himself denied any connection with bin Laden.The Chinese government has accused him of directing a series of violent terrorist activities including robbery and murder in Ürümqi on February 4, 1999 and violent murders in the Khotan region on December 14, 1999; it is believed that these attacks were carried out by an operative of his named Mutalif Kasim.