ISLAMABAD, Pakistan — The assassination of an outspoken secular politician by one of his elite police guards on Tuesday plunged the government deeper into political crisis and highlighted the threat of militant infiltration even within the nation’s security forces.

The killing of Salman Taseer, the prominent governor of Punjab Province, was another grim reminder of the risks that Pakistani leaders take to oppose religious extremists, at a time when the United States is pushing Pakistan for greater cooperation in the war in Afghanistan by cracking down on militant groups like the Taliban.

Read the complete story(Some news sites require registration)