There were some tough questions but few answers Thursday when MPs grilled a senior RCMP member about the deportation of a Canadian citizen to Syria.

U.S. authorities detained Maher Arar last year while he was changing planes in New York on his way home to Canada.

U.S. authorities suspected him of being a member of al-Qaeda and deported him to his native Syria, where he has been in jail ever since.

MPs of all parties on the foreign affairs committee wanted to know whether the RCMP shared any information about Arar with the Americans before he was detained.

But RCMP Assistant Commissioner Richard Proulx refused to answer.

Won't discuss it

"I am not prepared to discuss any operational matters on any cases, including Mr. Arar," he told the committee.

That angered MPs such as Conservative Bill Casey. He pointed out that Proulx already discussed the case earlier when he said the RCMP was not involved in the arrest.

"You've refuted those in your remarks and those are operational details," he said. "If you can refute those... you can answer our questions."

Liberal John Harvard said the RCMP has been on the case for more than a year and should clarify what it knows about Arar.

"Do you as a police force feel no obligation to assist this man, to clear this man's name?" he asked Proulx.

Arar's wife, Monia Mazigh, also appeared before the MPs Thursday and asked them to continue to push for answers.

A Bloc Qubcois MP introduced a motion to force Proulx to answer the questions, but the committee didn't vote on it.