National security adviser Samuel R. "Sandy" Berger said yesterday that U.S. law enforcement and intelligence agencies have been operating at "full tilt" since the arrest of an Algerian caught trying to smuggle bomb-making supplies into the country from Canada, but there is no evidence of other terrorist threats here.

"Now, we are not aware, at this point, of other specific threats against particular targets," Berger said on CBS's "Face the Nation." "But I would think that as Americans go about their plans for New Year's, they simply should be vigilant."

However, nervous U.S. officials are attempting to determine whether there is any connection between Saudi Arabian militant Osama bin Laden and Ahmed Ressam, 32, who was caught trying to cross from Canada into Washington state on Tuesday with 100 pounds of bomb-making supplies.

Even Ressam's arrest in Port Angeles, Wash., and recent crackdowns in Jordan and Pakistan against potential anti-U.S. terrorists "certainly don't eliminate the threat . . . and you don't know what else is being planned," another senior official said.

Pakistani authorities have arrested at least 80 people they fear may try to attack U.S. citizens in Pakistan, an intelligence official in Islamabad confirmed yesterday. Security at Pakistan's international airports has been tightened to try to track followers of bin Laden, who is based in Afghanistan, the official said.

The arrests were made during a series of overnight raids in northwestern Peshawar, which borders Afghanistan, and in the federal capital of Islamabad, they said. Most of those detained were Afghan nationals.

They have been held for interrogation following reports that bin Laden's supporters may attack American targets in Pakistan or use Pakistan as a transit route to other attack sites, said the official.

Similar arrests were made in Jordan in recent weeks.

"The detention of these people doesn't mean that they were about to launch a terrorist strike in Pakistan," said another intelligence official, who stressed that the arrests were "preventive in nature."

"With a sizable population of anti-U.S. religious elements in the country, we just can't take any chances," the official said.

Last month in Islamabad, six rockets were fired at U.S. and U.N. buildings. The attacks occurred two days before the United Nations imposed sanctions on Afghanistan's Taliban rulers because they refused U.N. demands that they hand over bin Laden for trial in either the United States or a third country on terrorism charges.

In Montreal, authorities found an orange van registered to Benni Norris, the name on a passport Ressam was carrying when he was arrested Tuesday, and a bomb squad searched the 1989 GMC. Nearby, on LaCordaire Street, a house authorities believed was associated with Ressam also was being searched by a bomb squad robot last night.

U.S. authorities are still attempting to locate an alleged accomplice of Ressam who apparently had been with him at a motel in British Columbia for three weeks before Ressam entered the United States.

Montreal police spokesman Andre Poirer said yesterday that a massive manhunt was underway in Canada and the United States for the suspected accomplice. "He might be returning to Vancouver," Poirer said. "He might be in Seattle. We don't know."

Ressam reportedly had two ferry ticket stubs in his possession--suggesting a companion may have walked off the boat--when he was arrested in Port Angeles, a port city of 20,000 about 60 miles northwest of Seattle.

Newsweek magazine, citing unnamed Canadian police sources, reported in this week's issue that Ressam lived in Montreal for a time with Said Atmani, who was extradited to Paris in connection with a 1995 subway bombing that killed four people and injured 86. The Paris bombing was attributed to an Algerian terrorist organization known as the Armed Islamic Group (GIA).

During his television appearance yesterday, Berger said he could cast no light on Ressam's motives, affiliation or intended target. Ressam had been denied refugee status by Canadian officials because of his alleged links to GIA.

Montreal police have said they are also investigating whether Ressam is linked to a theft ring in the city suspected of funneling money to radical Islamic groups around the world. Police in France and other European countries have cooperated with Montreal authorities in tracking some of the financial transfers to Islamic groups, according to a spokesman for the Montreal police.

Staff writer Vernon Loeb, correspondent Steven Pearlstein in Montreal and special correspondent Kamran Khan in Pakistan contributed to this report.