It is suspected that those responsible for the attack have links to al-Qaeda, and are seeking to oust Westerners from that country following the US Invasion of Afghanistan in 2001. On September 18, 2002, a man named Sharib Zubair was arrested and believed to have masterminded the attack. In 2003, two men were sentenced to death for the bombing by a Karachi court. The suspected bombmaker, Mufti Mohammad Sabir, was arrested on September 8, 2005.