The United Nations Monday temporarily closed all its offices in Pakistan after a suicide attack at the office of the World Food Program (WFP) in Islamabad, the UN chief in the country said. The bomber detonated his bomb in the lobby of the WFP headquarters and killed an Iraqi and two local woman employees, a UN statement said. 'In light of this incident all UN offices in Pakistan have been closed till further notice,' UN Pakistan Resident Coordinator Fikret Akcura said. Akcura condemned the attack and expressed deep sorry at the loss of lives and injuries of the World Food Program colleagues. 'This tragic and reprehensible attack is particularly deplorable given the fact that the UN staff have worked tirelessly to feed the impoverished and displaced persons in Pakistan,' said Akcura. 'There is no possible justification for this shocking crime against humanitarian workers here only to help the people of Pakistan,' he said. 'We urge Pakistani authorities to place their full attention on arresting the perpetrators who planned and implemented this horrendous act of terrorism, ' he added. The World Food Programme has been feeding up to two million beneficiaries, displaced by conflict since May 2009, the UN country head said. The UN statement said WFP also provides monthly food rations to some 100,000 people. It has a staff of around 500 international and national personnel. WFP has been providing food assistance to many poor families who face increasing prices due to the ongoing food crisis. 