A diplomatic battle has erupted between Washington and Ottawa over the deportation of a Canadian telecommunications engineer by U.S. officials who refuse to explain why he was arrested and sent to Syria.

"A person travelling on a Canadian passport is a Canadian citizen and has a right to be treated as a Canadian citizen," Foreign Affairs Minister Bill Graham said yesterday after delivering a speech in Montreal. "I have registered our protest to the United States."

Mr. Graham's complaint is the latest development in the mysterious case of Maher Arar, a 32-year-old engineer who was deported by U.S. immigration officials after being stopped at New York's John F. Kennedy Airport during a flight back to Canada after visiting family in Tunisia.

U.S. Immigration and Naturalization Services spokesmen said they had been ordered not to comment on what prompted Mr. Arar's arrest and deportation.

In Toronto yesterday, Paul Cellucci, the U.S. ambassador to Canada, also refused to comment on the case, except to say that officials had been justified in deporting Mr. Arar.

"All I can say is that the INS had good and sufficient reason for what they did, based on the current threat," Mr. Cellucci said.
Mr. Arar, who has been a Canadian citizen since 1987, was arrested at Kennedy Airport on Sept. 26, subjected to a series of lengthy interrogations, then deported to Syria, even though he was carrying a Canadian passport.

Mr. Arar's case is not the first to spark diplomatic friction over the handling of a Canadian citizen by U.S. officials. Omar Khadr, a 15-year-old Canadian, has been held by the United States in Afghanistan since July 27 without being charged. Mohammed Jabarah, 20, of St. Catharines, Ont., has been held in a U.S. prison since last June, also without being charged.

Shakir Baloch, a Pakistan-born doctor with Canadian citizenship, was returned to Canada this summer after being kept in a maximum security U.S. prison for four months. Despite diplomatic protests, Dr. Baloch was held without charge and released only after receiving clearance by the FBI.

Although U.S. officials have provided no rationale for holding and deporting Mr. Arar, Canadian sources say an acquaintance of Mr. Arar's may have led to his inclusion on a list of al-Qaeda suspects.

According to a well-connected Ottawa source, Mr. Arar was friends with a man in Ottawa's Syrian community who was targeted by RCMP investigators as part of a post-9/11 intelligence operation. As a result, Mr. Arar was also flagged and was questioned by the RCMP.

Whether this past association proves to be the link that resulted in Mr. Arar being detained and deported by U.S. officials remains to be seen, since they have so far refused to explain the background of the case, except to say that "immigration-related matters" are involved.

Mr. Arar, who lived in Montreal and Ottawa after coming to Canada as a teenager, is a well-known telecommunications engineer with credentials that include a masters degree. He is married with two children. He once spent a year working at a Boston-area software firm called Mathworks, where co-workers recall him as a talented and dedicated engineer.

One described him as "an up-and-up guy" and said he couldn't imagine him being accused of being a terrorist. Another acquaintance at an Ottawa software company said Mr. Arar was "a kind and decent guy -- if you were sick, he was the guy who would come over to help you get better."