A suicide bomber who killed five staffers at the UN food agency's headquarters in Pakistan on Monday was dressed as a security officer and allowed to enter the heavily guarded building after he asked to use the bathroom.
The United Nations announced it was temporarily closing all its offices in Pakistan after the midday Monday bombing, which blew out windows and left victims lying in pools of blood in the lobby of the three-story World Food Program compound.
"This is a heinous crime committed against those who have been working tirelessly to assist the poor and vulnerable on the front lines of hunger and other human suffering in Pakistan," UN Secretary-General Ban Ki-moon said in Geneva.
Despite the office closures, the UN said its Pakistani partner organizations would continue distributing food, medicine and other humanitarian assistance. The world body said it would reassess the situation over the next several days.