A senior analyst with Canada's national security service says Ottawa's Mohamed Harkat continues to pose a terrorist threat, even though he has been jailed for 34 months and his picture has been featured in newspapers across the country.

"It is our belief Mr. Harkat would continue to pose a threat to Canada, should he be released," the analyst, identified only by the initials P.G., told a Federal Court hearing into whether Mr. Harkat should be released on bail.

The Canadian Security Intelligence Service (CSIS) official noted that public notoriety did nothing to mitigate the threat posed by other al-Qaeda terrorists, including Egyptian-born Canadian Omar Said Khadr.

Mr. Khadr was arrested in Pakistan for the 1995 Egyptian Embassy bombing that killed 15 people, but was released after then-prime minister Jean Chretien made a personal appeal on his behalf. Mr. Khadr, who later became part of Osama bin Laden's inner circle, was killed in a firefight after the U.S. invasion of Afghanistan.

"The fact that his (Mr. Khadr's) case was so high profile had no effect on his decision to carry out Islamic extremism. ... It is clear that notoriety has little or no effect on a person's usefulness to the organization," said P.G., who serves as senior Middle East analyst at CSIS.

An al-Qaeda expert capable of working in 12 languages, including Arabic and Farsi, P.G. is also responsible for assessing the threat of Islamic extremism in Canada. He is the first CSIS official to testify in public during any phase of the Harkat security certificate case.

P.G. testified that long periods of incarceration have failed to ameliorate the threat posed by other Islamic extremists, noting that the architect of the March 11, 2004, bombings in Madrid had previously been imprisoned.

"It's our belief the dedication to the ideology is very strong and virtually impossible to break," he said.

Asked specifically about the case of Mr. Harkat, who has been detained on the strength of a government-issued security certificate since December 2002, P.G. said it is the security service's belief that the length of incarceration is irrelevant to someone committed to the use of violence in the defence of Islam.

The testimony came yesterday afternoon as the federal government, which is opposed to Mr. Harkat's bail application, began to call witnesses.

Mr. Harkat wants to be released under strict conditions, pending the outcome of a constitutional appeal that now appears headed to the Supreme Court of Canada. Similar appeals in two other security certificate cases have already been accepted by the high court.

More than 60 prominent Canadians have filed affidavits with the Federal Court, offering cash bonds in support of Mr. Harkat's bail application, including filmmaker Alexandre Trudeau and former NDP leaders Ed Broadbent and Alexa McDonough.

Mr. Harkat's lawyer, Matthew Webber, has said his client is willing to live with an electronic monitoring system, a curfew, a phone tap and supervision outside his home if released on bail.

A onetime pizza delivery man in Ottawa, Mr. Harkat has been under a deportation order to his native Algeria since March when Judge Eleanor Dawson upheld the government's opinion that he's an al-Qaeda terrorist. She based her decision largely on secret evidence.