Karachi residents sift through the debris of their burned-out neighbourhood, the morning after a bomb killed at least 45 people in Pakistan's commercial capital.<br/> <br />A suspected suicide bomber attacked Shi'ite Muslims as they were leaving a mosque on Sunday.<br/> <br />Pakistan has seen fewer suicide attacks on government and military targets over the past year.<br/> <br />But killing on the streets of Karachi points to a new type of threat.<br/> <br />A campaign led by the al Qaeda-linked Lashkar-e-Jhangvi and allied Pakistani anti-Shi'ite groups to rip open sectarian fault lines in the city of 18 million.<br/> <br />Residents of the city say they are under siege by Lashkar-e-Jhangvi death squads who seem to act with impunity.<br/> <br />(SOUNDBITE) (Urdu) LOCAL RESIDENT GHULAM ABBAS SAYING:<br/> <br />"We do not know what is to become of this country. The government is quiet. It is standing around like a spectator. You are seeing what is happening to Muslims. A person can not leave his house without wondering w
