Canadian police said Tuesday they had told U.S. authorities they had no evidence an Ottawa software engineer was an Al Qaeda agent before Washington deported him to Syria , where he was tortured.

Royal Canadian Mounted Police Commissioner Giuliano Zaccardelli said police initially told U.S. authorities Syrian-born Maher Arar was a "man of interest" and may have ties to Islamic extremists but they later told Washington they had no evidence to support those allegations.

Yet U.S. authorities went ahead and deported Arar to his native Syria, where he says he was tortured into making false confessions, Zaccardelli told a public security hearing in the capital Ottawa.

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"RCMP investigators clearly informed U.S. officials that there was no evidence to support criminal charges against Mr. Arar in Canada, that he could not be prevented from entering Canada, and that we were unable to link him to Al Qaeda," Zaccardelli said.

The 34-year-old Arar was traveling on a Canadian passport in 2002 when he was detained at New York's Kennedy Airport during a stopover on his way home to Canada from a vacation in Tunisia. Without informing Canada, the U.S. government turned Arar over to Syria where he was tortured, tossed in a small cell and finally released after nearly a year of confinement.

After his release from a Damascus prison in 2003, Arar made detailed allegations about whippings with electrical cables and Canadian authorities determined his account was credible.

Arar was exonerated of all suspicion of terrorist activity in September by a Canadian government commission. He has become the best-known case of extraordinary rendition -- the U.S. transfer of foreign terror suspects without court approval to third countries where they can be subjected to torture.

Canadian Prime Minister Stephen Harper last month demanded a formal apology from the White House, saying Arar had been unfairly deported to face torture in Syria and that American officials "had not been candid and truthful" in dealing with Canadian authorities.

Secretary of State Condoleezza Rice in October wrote a letter to the Canadian government assuring Ottawa that the United States would not unilaterally send Canadian citizens to third-party countries for questioning about terrorist activities.

There was no apology for the Arar affair in the letter, but Ottawa said it was satisfied.

In September, State Department spokesman Sean McCormack said "the people who made the decisions at the time ... determined a couple of things: One, that this individual posed a threat to the United States based on the information that they had; and two, that they were able to assure themselves, they had the reasonable expectation that this individual was not going to be maltreated."

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