A truck filled with some 1,000 kilograms of explosives rammed into the front gate of the five star Marriott Hotel in Islamabad, Pakistan today, killing at least 60 people and injuring some 200 others. The 290 room hotel is a popular location for foreign envoys and the Danish Foreign Ministry confirmed that one of its diplomats was among the casualties.

The attack occurred just hours after Pakistani President Asif Ali Zardari addressed parliament about the problems of rising militancy in the country. At the time, the President along with Prime Minister Gilani and General Kayani were among those having dinner at the Prime Minister’s Secretariat, very near the site of the blast. It does not appear anyone at the dinner was harmed, however.

So far it is unclear who was responsible for the blast, but between Pakistan’s military offensive in Swat Valley and the American air strikes in Waziristan there are plenty of candidates. Witnesses say that the bombers issued a warning three minutes before the attack advising people outside the building to “run away and save their lives”.

Also unclear is the reason for the attack. Asian News International claims the militants had been tipped off to the presence of several high ranking CIA officials staying in the hotel. The Indo-Asian News Service, by contrast, cites security officials who said that 30 US Marines had been staying in the hotel, and were scheduled to leave for Afghanistan tomorrow morning. They also say police sources told them one American was among those killed in the attack.

Pakistani Foreign Minister Mehmood Qureshi expressed shock at the attack, and said his government will continue to cooperate with international forces to fight terrorism.