Al Qaeda's No. 2 leader was invited to dinner marking an Islamic holiday at the Pakistani border village struck by a purported CIA airstrike, but he did not show up, intelligence officials said Sunday, as Islamic groups demonstrated across the country in protest of the 17 people killed in the missile strike.

The two Pakistani officials told The Associated Press that this could explain why Friday's predawn attack missed its apparent target, Ayman al-Zawahiri, Usama bin Laden's top lieutenant.

Al-Zawahiri sent some aides to the dinner instead and investigators were trying to determine whether they had been in any of the three houses that were destroyed in the missile strike that killed at least 17 people, one of the officials said.

The new details emerged as Islamic groups held nationwide protests and anger mounted over the attack that Pakistan says killed innocent civilians while al-Zawahiri was not even there.

The intelligence officials, who spoke on condition of anonymity because of the sensitivity of the issue, said al-Zawahiri, who has a wife from a local tribe, had been invited to a dinner in the village to mark the Islamic holiday of Eid al-Adha but changed his mind and sent some aides instead.

Pakistani officials have strongly condemned the strike on the ethnic Pashtun hamlet of Damadola, about four miles from the border with Afghanistan.

A senior army official told The Associated Press on Sunday that "foreigners" were reported in the area around Damadola, which is four miles from the Afghanistan border, but he said there was no information al-Zawahiri was among them.

Many in this nation of 150 million people oppose the government's participation in the U.S.-led war against international terrorist groups, and there is increasing frustration over a recent series of suspected U.S. attacks along the frontier aimed at militants.

Reflecting the anger, Islamic groups staged demonstrations across Pakistan on Sunday to denounce the attack in Damadola.

Some 10,000 people rallied in Karachi, Pakistan's biggest city, chanting "Death to America" and "Stop bombing against innocent people." Hundreds massed in the capital, Islamabad, and in Lahore, Multan and Peshawar burning U.S. flags and demanding the withdrawal of U.S. troops from Afghanistan.

Counterterrorism officials in Washington have declined to comment on the airstrike, but a large number of Al Qaeda and Taliban combatants, including al-Zawahiri and bin Laden, are believed to have taken refuge in the rugged mountains along on the Afghan-Pakistani border.

Pakistani officials insist they do not allow the 20,000 U.S. soldiers in Afghanistan to cross the border in the hunt for Taliban and Al Qaeda fighters.

In a speech shown Sunday on state-run Pakistan Television, President Gen. Pervez Musharraf did not address the Damadola strike directly, but he warned his countrymen not to harbor militants, saying it would only increase violence inside Pakistan.

"If we keep sheltering foreign terrorists here ... our future will not be good. Remember what I say," Musharraf said in the speech, which was made Saturday in the northwestern town of Sawabi.

Survivors in Damadola denied militants were there, but some news reports quoted unidentified Pakistani officials as saying up to 11 extremists were believed among the dead.

A senior intelligence official said Sunday that 12 bodies, including seven foreigners, had been taken from the village.

He said the bodies were reclaimed by other militants, but another Pakistani official told AP on Saturday that some were taken away for DNA tests. A law enforcement official in Washington said the FBI expected to conduct the tests to determine victims' identities, although Pakistan had not yet formally requested them.

The claims by the officials, who spoke on condition of anonymity because of the sensitivity of the matter, could not be independently verified.

Meanwhile, the governor of the Afghan province across from Bajur region, where Damadola is, said Afghanistan's government had formed a 1,000-man tribal militia to watch the border.

"Al Qaeda, as well as the Taliban and other militants have camps over the border," Kunar Gov. Assadullah Wafa said.

He said the new force made up of young men from villages in the area would "hopefully make it harder for the militants" to slip across the frontier.

"But the border is so long and so rugged that it's easy for them to come and go," he conceded.