A huge truck bomb devastated the Marriott Hotel in Pakistan's capital Saturday, creating a chaotic, fiery scene as rescue crews searched for survivors. At least 60 people reportedly have been killed, including one American.
Interior Ministry chief Rehman Malik said the Czech ambassador to Pakistan was also among the dead.
The blast left a 30-foot deep crater in front of the main building, where flames poured from the windows and rescuers ferried a stream of bloodied bodies from the gutted building — which was in danger of collapsing.
The five-floor Marriott in Islamabad is a favorite place for foreigners as well as Pakistani politicians and business people to stay and socialize, despite repeated militant attacks. It served as the de facto back office for the international media during the 2001 war against the Taliban in neighboring Afghanistan.
More than a hundred were injured, and two hospitals told the Associated Press that 10 foreigners were among those in their treatment, including one each from Germany, Saudi Arabia, Morocco and Afghanistan.
A hospital official told FOX News that one unidentified American was among the dead, and Al Jazeera reported that five Americans were wounded in the blast.
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President Bush, in a written statement, also said at least one American had been killed. He condemned the bombing while expressing his support for the governmnet of Pakistan.
"This bombing, the latest in a series of terrorist attacks, is part of a continuing assault on the people of Pakistan. This attack is a reminder of the ongoing threat faced by Pakistan, the United States, and all those who stand against violent extremism. We will assist Pakistan in confronting this threat and bringing the perpetrators to justice," Bush said.
Senior Police Official Asghar Raza Gardaizi said the blast, which reverberated throughout Islamabad, was caused by more than 2,204 pounds of explosives.
Police sought in vain to shoo away bystanders and reporters for fear of gas leaks and that the building might collapse. Army engineers were heading to the scene to help look for anyone trapped in the rubble.
The attack came hours after new President Asif Ali Zardari addressed Parliament for the first time and underscored the fragility of his administration as the country finds its footing after a decade of military rule.
Leaders of Pakistan's civilian government stated their determination to combat terrorism, though the country's seven-year alliance with the United States has come under strain over U.S. threats to attack militants in the lawless tribal areas bordering Afghanistan.
Zardari and Prime Minister Yousuf Raza Gilani strongly condemned the attack in a statement.
"This is terrorism and we have to fight it together as a nation," Malik told reporters at a hospital overflowing with the injured.
Witnesses and officials said a large truck rammed the high metal gate of the hotel at about 8 p.m., when the restaurants would have been packed with diners, including Muslims breaking the Ramadan fast.
Gardaizi said rescuers had counted at least 40 bodies, and he feared that there "dozens more dead inside." Many of the dead were security personnel.
Witnesses spoke of a smaller blast followed by a much larger one.
A U.S. State Department official using a section of white pipe as a walking stick led three colleagues through the rubble from the charred building, one of them bleeding heavily from a wound on the side of his head.
One of the four, who identified himself only as Tony, said they had begun moving toward the rear of the Chinese restaurant after the first blast when the second one threw them against the back wall.
"Then we saw a big truck coming to the gates," he said. "After that, it was just smoke and darkness."
U.S. embassy spokesman Lou Fintor said officials were trying to account for embassy staff and any other Americans affected. He said he had no other details.
Ambulances rushed to the area, picking their way through the charred carcasses of vehicles that had been in the street outside. Windows in buildings hundreds of meters away were shattered.
Mohammad Sultan, a hotel employee, said he was in the lobby when something exploded, he fell down and everything temporarily went dark.
"I didn't understand what it was, but it was like the world is finished," he said.
Tropical fish from the tanks inside lay among the torn furnishings in the entrance area. Scorched tree limbs from trees near the hotel were tossed hundreds of yards.
Malik told the AP that it was unclear who was behind the attack, but that authorities had received intelligence that there might be militant activity due to Zardari's inaugural address to Parliament earlier Saturday. Security had been tightened, he said.
In his speech, Zardari vowed not to let terrorists use Pakistani territory. However, he also warned that the government would not allow "any power" to violate Pakistan's sovereignty — a reference to U.S. strikes across the border from Afghanistan that Pakistani officials warn will fan Islamic extremism.
Pakistan has faced a wave of militant violence in recent months following army-led offensives against insurgents in its border regions, including several in the capital.
In July, a suicide bombing killed at least 18 people, most of them security forces, and wounded dozens in Islamabad as supporters of the Red Mosque gathered nearby to mark the anniversary of the military siege on the militant stronghold.
In June, a suicide car bomber killed at least six people near the Danish Embassy in Islamabad. A statement attributed to Al Qaeda took responsibility for that blast, believed to have targeted Denmark over the publication of cartoons depicting the Prophet Muhammad.
In mid-March, a bomb explosion at an Italian restaurant killed a Turkish woman in the capital, and wounded 12 others, including four FBI officials.
IntelCenter, a group which monitors Al Qaeda communications, said senior Al Qaeda leader Mustafa Abu al-Yazid, who claimed the Danish Embassy bombing, threatened additional attacks against Western interests in Pakistan in a video timed to the recent anniversary of the Sept. 11 attacks.
FOX News's Scott Heidler and The Associated Press contributed to this report.