Embarrassed Canadian officials were scrambling today to explain how a suspected Algerian terrorist managed to elude them for nearly six years before getting caught by U.S. border police as he allegedly tried to smuggle a homemade bomb into Seattle last week.

Documents released this week in Ottawa and Montreal tell a tale of bungling by police and immigration officials as well as skillful manipulation of Canada's open-armed immigration system by the mysterious Algerian, Ahmed Ressam.

The revelations prompted criticism from Canadian legislators that echoed complaints long expressed privately by U.S. officials that lax border controls and open immigration policies have combined to make Canada an easy route on the way to the United States for terrorists, drug traffickers and illegal immigrants.

Ressam arrived in Canada in February 1994 with a fake French passport and a criminal record for illegal arm sales. But immigration officials acknowledge that it took them nearly four years to issue an arrest warrant and deportation order for Ressam despite his repeated failures to show up at hearings on his petition for refugee status.

Even after the deportation order was issued, Montreal police apparently released Ressam from custody after he completed a two-week jail term for theft.

Then, in February, the Foreign Ministry issued him a passport under the name of Benni Noris, according to a report in today's Globe & Mail. This is the name Ressam used to get a driver's license, register a van, rent an apartment and obtain a permit to operate a convenience store.

"Our system is a sieve," complained Leon Benoit, a member of the opposition Reform Party in the House of Commons.

"Bumbling crime control," declared the editorial in this morning's National Post.

Following a cabinet meeting on Monday, Prime Minister Jean Chretien said Canada's protections against terrorists were "adequate."

"When you are receiving 250,000 [immigrants] a year," he said, "there might be some people who come that don't have the best intentions."

And Derik Hodgson, a spokesman for the minister of Citizenship and Immigration, charged that "a note of hysteria" had surrounded media coverage of Ressam's arrest and the alleged prospect of millennial terrorism.

Immigration officials today confirmed that Ressam arrived at Montreal's Mirabel Airport in February 1994 with a fake passport and immediately petitioned for refugee status, as many Algerians had following the outbreak of civil war between the government and Islamic extremist groups.

Ressam claimed that he had been arrested in 1992 by Algerian police, who accused him of selling guns to the rebels--a charge he denied. He claimed he was held in prison for 15 months, during which he was tortured until he signed a confession. Upon release from jail, he said he fled to Morocco, Spain and France before coming to Canada.

But when it was time for a hearing on his refugee claim, Ressam did not show up--and in July 1995 the first of several deportation orders was issued. His lawyer appealed the order to federal court, but by the time the appeal was dismissed six months later, Canada had adopted a blanket policy of not deporting people to Algeria. Instead, Ressam was ordered to check in with an immigration officer once a month.

Within a year, Ressam was again missing his appointments, and another deportation order was issued in May 1998.

Four months later, Ressam was arrested by Montreal police for stealing a computer from a car. But when his two-week jail term was over, he was released. Today, Montreal officials refused to answer questions on whether they checked for outstanding warrants before his release.

At about the same time, according to unidentified sources quoted by the Globe & Mail, Ressam applied for a passport under the alias Benni Noris, submitting a forged baptismal certificate, which is accepted in lieu of a birth certificate at passport offices in the heavily Roman Catholic province of Quebec. Investigators believe Ressam used the false passport to travel to South Korea and Los Angeles.

Also under the Noris name, Ressam rented a vacant storefront on LaCordaire Street, in the city's East End, and obtained a permit from city hall to operate a convenience store. Neighbors told the Montreal Gazette they saw Ressam and several other men lugging in merchandise in recent weeks from an orange van, which police later confirmed was registered to Noris. The Royal Canadian Mounted Police searched both the van and the store on Sunday night but declined to comment today on any evidence they might have found.

One focus of the Canadian investigation of Ressam is his relationship to Karim Said Atmani, his one-time roommate in Montreal who has dual Algerian and Bosnian citizenship. Intelligence officials believe Atmani is part of an Islamic terrorist network operating in Europe. Canadian investigators believe Atmani may have been Ressam's control officer in Montreal, where Atmani lived for several years before being expelled in October 1998 for being in the country illegally, according to an immigration department spokesperson. Police are investigating reports that he may have reentered Canada and been with Ressam during his three-week stay in Vancouver last month.

Officials on both sides of the border have long worried about Canada as a point of entry for terrorists targeting the United States.

A report by the U.S. Justice Department last year faulted Canada for allowing convicted terrorist Gazi Ibrahim Abu Mezer to enter Canada on a student visa in 1993 without checking his arrest record in Israel. Mezer entered the United States from British Columbia and was arrested and sentenced to life in prison for plotting to plant a bomb in the New York City subway.

And in Washington this week, Rep. Lamar S. Smith (R-Tex.), chairman of the House Judiciary subcommittee on immigration, said the country was at risk "as long as terrorists can exploit Canada's immigration laws and penetrate the thinly guarded U.S. border."

"The open nature of our society and the related policies concerning refugees and immigrants make us particularly vulnerable to terrorist influences and activities," Director Ward Elcock of the Canadian Security Intelligence Service, Canada's CIA, told a panel of the Canadian Senate this year.

The CSIS also issued a report in July noting that there are more international terrorist organizations active in Canada than any country in the world except the United States. It said those groups have had a "direct or indirect association" with the bombing of the World Trade Center in New York, suicide bombings in Israel, assassinations in India and the bombing of a U.S. military apartment complex in Saudi Arabia.

The Chretien government disputes that there is any link between the amount of terrorist activity in Canada and its immigration laws.

CAPTION: Freddy Zouki, an Algerian who works in Montreal, reloads his minivan after an inspection by U.S. Customs agents at the border crossing near Detroit.