The blast left a vast crater some 20 feet deep and 30 feet wide in front of the main building where flames leapt from the windows and rescuers ferried a stream of bloodied bodies from the gutted building.
Prime Minister Yousuf Raza Gilani was hosting an Iftar dinner at the nearby Prime Minister's Secretariat. The event was attended by President Asif Ali Zardari and Army Chief Ashfaq Parvez Kayani. There was no reports of anyone being injured at the Prime Minister's Secretariat.
A Pakistani firefighter attempts to extinguish the burning facade of The Marriott Hotel in Islamabad.
Photographs: Farooq Naeem/AFP/Getty Images
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