A suicide bomber dressed as a paramilitary soldier attacked an office of the UN World Food Program (WFP) in the Pakistani capital Monday killing five people and wounding several, officials said. “I went to my office on the first floor and as I sat on my chair there was a huge blast,” WFP official Arshad Jadoon told Reuters outside the tightly guarded office in a residential area of Islamabad. “All of a sudden, a smoke cloud enveloped the building and we came out where wounded people were lying,” Jadoon said. Divulging initial findings, Pakistani Interior Minister Rehman Malik told newsmen that the bomber disguised as a paramiliary soldier entered the WFP compound after asking a guard at the gate if he could use a toilet. Around 80 people, including diplomats, were present when the attacker detonated the bomb. Police said one foreigner, an Iraqi, was among the dead while the WFP said three of its staff had been killed and several wounded. The United Nations has announced temporary closure of all its offices across Pakistan after the blast. The WFP office was well-protected as a 15-feet wall had been erected around it with barbed wires and security cameras installed. President Asif Ali Zardari's private residence is also situated in the vicinity. More attacks likely “They are like wounded snakes,” Malik said. “We expected they would attack some specific places to put the government under pressure.” An eyewitness, Sajjad Anwar, who is working as telecom assistant with the WFP, told newsmen that the office had received no threat of an attack. He said that security measures around the office were excellent. Private security guards were on duty apart from police and Frontier Constabulary, he said. Qouting recent intelligence reports, Malik said that some five days back those terrorists had threatened to retaliate to avenge the operations in Swat and other areas. The arrested Taleban leaders, he said, had also disclosed during investigations that their group had deputed people to hit different targets. “In a matter of a few days we'll take action against them as we took in Swat, Bajaur and Mohmand,” Malik said, referring to three northwestern areas where the security forces have attacked and pushed back the militants. He did not elaborate. Malik also praised the WFP for its support to the IDPs.