ISLAMABAD - A suicide bomber dressed as a paramilitary soldier attacked an office of the U.N. World Food Programme (WFP) in the Pakistani capital on Monday, killing five staff members, government and U.N. officials said.

Pakistan is battling al Qaeda-linked Islamist militants who have set off numerous bombs in towns and cities aimed at security forces and government and foreign targets.

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, he said.

A WFP spokesman, Amjad Jamal, said five members of staff had been killed, four Pakistanis and an Iraqi. At least two of the Pakistanis were women.

U.N. Secretary-General Ban Ki-moon said the attack was a heinous crime.

This is a terrible tragedy for the U.N. and for the whole humanitarian community in Pakistan, he said in a statement condemning the bombing in the strongest terms and issued in Geneva where he is on a two-day visit.

The United Nations temporarily closed its office in Pakistan after the blast for security reasons, a U.N. spokeswoman said.

Two foreign U.N. workers were killed in a suicide car bomb attack on a hotel in the northwestern city of Peshawar in June.

The blast led to a brief spate of selling at Pakistan's main stock market.

There was slight profit-taking immediately after the news broke but the market quickly recovered, said Sajid Bhanji, a dealer at brokers Arif Habib Ltd.

MORE BOMBS EXPECTED

The army has made progress against militants in the northwest and Interior Minister Rehman Malik says the back of the Pakistani Taliban has been broken.

But the militants have struck back with several bomb attacks in recent days as the army prepares to launch an offensive on the Pakistani Taliban's main bastion in the South Waziristan region on the Afghan border.

The bomber was disguised as a paramilitary soldier and got into the WFP compound after asking a guard at the gate if he could use a toilet, Malik told reporters at the scene.

They are like a wounded snake, Malik said. We expected they would attack some specific places to put the government under pressure.
Captured militants had told interrogators some bombers had been sent off on missions last month, Malik said. So in coming days, two or three suicide bombings are expected, he said.

Malik said the bombers were trying to destabilize the country but the nation was united against them.

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 security forces have attacked and pushed back the militants. He did not elaborate.

The WFP provides food to millions of impoverished Pakistanis.

The agency was recently involved in providing relief to about 2 million people displaced by an army offensive against militants in the Swat valley.

There was no claim of responsibility for the attack on the WFP office, which is several hundreds meters (yards) from the Islamabad home of President Asif Ali Zardari.

Zardari moved into the official presidential residence soon after his election last year for security reasons.

(Additional reporting by Zeeshan Haider and Sahar Ahmed; Writing by Robert Birsel; Editing by Sugita Katyal)

Pakistan