Islamabad - Rescuers clawing through the rubble of a bombed luxury hotel in Pakistan's north-western city of Peshawar on Wednesday recovered six more bodies, taking the death toll to at least 18, officials said.
The United Nations evacuated most its foreign staff from the city, while United States' consulate personnel were instructed to limit their movements until further notice.
A portion of the Pearl Continental hotel, a popular haunt for foreigners and the local elite in the heart of the city, collapsed Tuesday night when at least three suicide attackers penetrated security at its gates and detonated a car bomb outside the lobby.
The United Nations office in Islamabad said two staff members - Aleksandar Vorkapic from the UN High Commissioner for Refugees and Perseveranda So of UNICEF - were among the dead.
At least 64 people, including four UN staffers, were wounded.
No group immediately claimed responsibility for the attack, but it bore similarity to another bombing in Pakistan's eastern city of Lahore last month which was later claimed by the Taliban.
Security camera footage of Tuesday's blast showed hotel guards clearing a sedan for entry into the compound when a pickup truck drove behind it.
As the hydraulic barrier was lowered, shots were fired and both vehicles moved quickly through the passage and soon there was a flash and a cloud of smoke with no vehicles in the frame.
Shafqatullah Malik, deputy police chief in North-West Frontier Province of which Peshawar is the capital, said the pickup truck carried nearly 500 kilograms of high-intensity explosives.
The massive blast damaged the hotel façade, destroyed dozens of vehicles in the parking lot and shattered windows of buildings several hundred meters away from the site.
'Six bodies have been recovered since morning,' Qazi Jameel, a senior police officer coordinating the rescue and relief operations, told the German Press Agency dpa over the phone.
'No one has been pulled out alive but there's still debris to be removed,' Jameel said, adding that the casualty count might increase.
UN Secretary General Ban Ki-moon condemned the attack as an action 'which no cause can justify,' according to a statement from the world body.
The car bombing was the latest in a series of attacks carried out by militants in recent weeks to avenge a military operation against their comrades elsewhere in the province.
Pakistan launched a concerted campaign in the Swat Valley and its neighbouring districts in late April to rout Islamist insurgents who moved into neighbouring districts after being emboldened by a peace pact under which the government introduced strict sharia, or Islamic law, in parts of the province.
Vast support from local political parties and the local population has encouraged the government to push on with its offensive, but a mass exodus of refugees and an ensuing humanitarian crisis are threatening a change in opinion.
More than 2.5 million people have fled the fighting since May 2. They have been taken in by family and camps run by the government with the support of UN agencies.
But these relief activities can be hampered due to the lethal attack on the hotel.
Ishrat Rizvi, an official at the UN information office in Islamabad said most of the foreign staff had been 'moved out' of Peshawar mainly due to security concerns while some are being shifted because they are 'traumatized.'
The UN World Food Programme (WFP), which is distributing food rations at humanitarian hubs and refugee settlements, delayed resumption of its operations until Friday.
However, United Nations Resident Coordinator in Pakistan Fikret Akcura, said Wednesday the world body was determined to continue humanitarian support to Pakistanis uprooted by Swat offensive.
A statement from the US embassy in Islamabad said its consulate personnel in Peshawar have been instructed to limit their movements until further notice.
Pakistan's national airline PIA cancelled all its domestic and international flights to and from Peshawar, where airline's one pilot was also killed in the bombing.
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