Pakistan's Interior Ministry has linked Al-Qaeda-connected Taliban militants to the hotel bombing that has left scores dead.
The suicide truck bombing on September 20 at Islamabad's five-star Marriott Hotel killed at least 53 people and injured as many as 270 others. No group has so far accepted responsibility for the attack.
Rehman Malik, the top Interior Ministry official, said, "I am not in a position to tell who has done it. But previously all the investigations...all the roads have gone to South Waziristan," referring to tribal areas where Al-Qaeda and the Taliban are active.
Pakistani Defense Minister Chuadhry Ahmad Mukhtar told journalists in Islamabad that he believed that foreigners were involved in the attack.
"I will say that there will definitely be a foreign hand in this [attack]. Because the Uzbeks and Chechens against whom we are fighting are not Pakistanis," Mukhtar said.
He said government forces were already fighting against Uzbek, Chechen, and Arab militants in the Federally Administered Tribal Areas (FATA) and the Northwest Frontier Province (NWFP) along the western Afghan border.
Situated in the heart of Islamabad, the six-story Marriott Hotel is now a gutted ruin. Popular among foreigners and wealthy Pakistanis, the hotel is close to the parliament and the official residences of the Pakistani president and prime minister.
According to a RFE/RL Radio Free Afghanistan's correspondent in Pakistan, Najib Aamir, fire services had to battle the flames engulfing the hotel for 13 hours before they extinguished the blaze.
Rescuers spent the day combing the building for survivors. Most of the victims were Pakistani, but included at least four foreign nationals, among them two Americans, and a Vietnamese citizen. Another 11 foreigners were injured in the attack.
The Czech Foreign Ministry has confirmed that its ambassador to Pakistan, Ivo Zdarek, was among the dead. The Danish Foreign Ministry has said that one of its diplomats is missing.
With shocked Pakistanis now referring to a September 20 hotel bombing that killed scores as their 9/11, the country's leaders are pledging to fight terrorism with new vigor.
In a televised address to the nation on September 21, President Asif Ali Zardari said that terrorism was "a cancer in Pakistan which we will root out."
"We will not be afraid of these cowards. No Muslim can commit such an atrocity in the holy month of Ramadan. Those who are spilling the blood on Muslims are not Muslims. And no religion allows such an atrocity," Zardari said.
Farzana Raja, a member of the National Assembly of the lower house of the Pakistani parliament from the governing Pakistan People's Party, told RFE/RL that the mood in Islamabad was sad and somber.
"We feel very sad but at the same time, we are together as a nation. And we have this courage and devotion to combat the terrorism and terrorists," Raja said.
She maintained that the timing of the attack was significant because it came on the same day when the transition to democracy in the country was completed with the newly elected president's address to a joint session of the national parliament.
In that September 20 speech, President Zardari said he will not allow Pakistan's territory to be violated by terrorists or foreign powers.
"I ask of the government that it should be firm in its resolve, not allow the use of its soil for carrying out terrorist activities against any foreign country. We will not tolerate the violation of our sovereignty and territorial integrity by any power in the name of combating terrorism," Zardari said.
Opposition parties in Pakistan have said the security policies of the past governments have turned the country into a "terrorist target."
Raza Mohammad Raza, a member of the Senate, the upper house of the national parliament from the opposition Pashtunkhwa Milli Awami Party, blamed the current situation on the country's past and present security policies, which have used Islamist militant groups as proxies in neighboring Afghanistan and India.
"The real tragedy is that their policy is still that the terrorists should prevail and they should be nurtured and trained," Raza said. "In our state today, there are elements and powerful quarters who are still supporting the terrorist infrastructure and they defend the terrorists in one or other way. The destruction of terrorist networks depends on Pakistan's resolve. It depends on their decision."
The Marriott Hotel bombing has been widely condemned internationally. The Pakistani government has ordered a top-level inquiry.
The issue of terrorism is expected to top the agenda as Zardari meets U.S. President George W. Bush and other leaders in New York this week. There have been tensions of late between Pakistan and the United States over U.S.-led raids against militants in Pakistan.
RFE/RL Radio Free Afghanistan correspondent Najib Amir and Barakwal Miakhel contributed to this report from Pakistan