Islamabad: Three UN officials have been killed and six others injured in a blast outside the United Nations World Food Programme office in Islamabad.
Islamabad is on high alert after the explosion, which has partially damaged the building.
UN officials and people in nearby buildings were asked to evacuate the area following the blast.
No one has so far claimed responsibility for the attack.
The World Food Programme office is located a short distance from Zardari House, the private residence where Pakistan People's Party chief Asif Ali Zardari lived before becoming President, some police offices and the district administration and the district courts.