ISLAMABAD, Pakistan — A suicide bomber disguised as a Pakistani security officer attacked the lobby of a heavily guarded and fortified U.N. office in Islamabad on Monday, killing five other people and heightening fears of renewed violence in Pakistan's capital after a long lull in suicide attacks.
The midday bombing occurred at the Islamabad headquarters of the World Food Program. Dressed in the uniform of a paramilitary police officer, the bomber asked a security official at the agency's main gate for permission to use the restroom, said Pakistani Interior Minister Rehman Malik.
Once he reached the reception area, he detonated about 18 pounds of explosives. The five victims were World Food Program employees: two Pakistani women, two Pakistani men and an Iraqi man. At least six others were injured, two of them critically.
Susan Manuel, spokeswoman for the U.N. office in Islamabad, said the organization would close its offices in Pakistan temporarily while it reviews security.
The blast was the first suicide bombing in Islamabad since June, when an assailant scaled a wall at a police station and killed two police officers.
Since then, the Pakistani government has strengthened its security measures in the capital, and violence attributed to militants has subsided. However, as the Pakistani military readies a major ground offensive to root out Taliban militants from the country's volatile Waziristan region along the Afghan border, Taliban leaders have been vowing to strike back with suicide attacks in major Pakistani cities.
There was no immediate claim of responsibility for the attack, and it was unclear why the World Food Program was targeted.
Malik said he had recently warned governmental bodies and the offices of foreign institutions to be on high alert after receiving intelligence reports that militants might strike by disguising themselves in security uniforms or traveling in official vehicles.