Prime Minister Stephen Harper won't confirm reports that the RCMP and Ottawa's top-secret Joint Task Force 2 commandos played a role in the rescue of three Western peace workers who had been held hostage in Iraq for almost four months.

Canadians James Loney, 41, and Harmeet Singh Sooden, 32, were freed along with Briton Norman Kember, 74, during a raid by multinational forces northwest of Baghdad on Thursday morning.

Prime Minister Harper comments on rescue of hostages on Thursday

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Pentagon sources have told CBC News that Canadian special forces were involved in the operation, but it's not clear who took part or what their role may have been.

Thursday afternoon, RCMP Sgt. Martin Blais said, "I can comfirm we were there, working in collaboration with DND, foreign affairs and our international partners."

British Foreign Secretary Jack Straw (AP photo)

For operational reasons, and to protect operational security, he would not elaborate.

There have been reports that JTF2 commandos, based at Dwyer Hill in Ottawa's west end, had been working in Iraq. It's believed they worked in tandem with Britain's elite Special Air Service (SAS).

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Ayub Nuri, a reporter for Global Radio News in Iraq, said Thursday that Canadian police agents were involved in the operation.

The Department of National Defence has not commented on those reports. In a midday address to public service workers in Ottawa, Harper said Canadian agencies were involved on the ground, but didn't offer any specifics.

He offered thanks to "a number of Canadian departments and agencies that worked on this delicate operation with their British, American and Iraqi counterparts, and played an important role in ensuring the success of this operation.

"You did excellent work, and Mr. Loney and Mr. Sooden asked me to thank you for the assistance," said Harper, who spoke to the two former hostages earlier in the day.

Harper refused to say whether Canada's elite commando squad, JTF2, is operating in Iraq, citing national security. He did say, however, that it should be no surprise that Canadians are in Iraq.

"There have been a small number of Canadian military personnel embedded in American and allied units. That's been the case since the beginning of the war. Nothing has changed on that front," he said.

The prime minister said he hadn't known exactly when the rescue operation would take place, but he did have some indication days ago that it was in the works.

Harper also thanked "our British and American allies" for their "exceptional" role in the rescue.

RCMP involved, said Straw

While making the announcement of the hostage's release earlier Thursday in London, British Foreign Secretary Jack Straw said the RCMP were involved in the raid northwest of Baghdad.

"The operation included representatives from the Royal Canadian Mounted Police, other agencies from Canada – and they did a terrific job – as well as the Americans and British staff and those from Iraq," said Straw.

The RCMP has not confirmed its involvement.

Straw said other "Canadian personnel" played a role.

"It's the result of a team effort between military and civilian personnel, including Canadian personnel who I was able to meet," he said.