OTTAWA - Special forces in both Canada and the United States are taking a close look at Canadian-made mini-submarines for the murky world of covert operations.

The cutting-edge subs, some of which are built in Canada, are seen by some in the U.S. Special Forces community as essential for specialized top-secret operations against threats such as al-Qaida in coastal countries.

One defence source in Washington, who spoke on background, said the U.S. Navy has been impressed with the submarine rescue system it purchased a few years ago from B.C.-based International Submarine Engineering, which also sells 7.6 metre submersibles capable of carrying a handful of soldiers.

The elite, secretive U.S. Special Forces is interested and also believes the subs would "be an ideal fit" for their Canadian counterparts, said the source, who was not authorized to speak publicly.

No program has been requested or planned, however, said Brig.-Gen. Denis Thompson, the commander of Canada's special forces.

"It is an area of interest," Thompson said in an interview with The Canadian Press. "It is potentially another tool for the toolbox."

Domestic concerns and the safety of the highly trained soldiers were some of the reasons Thompson asked staff to examine the boats in the spring of last year.

Rather than operating in waters far from home, the military is concerned about missions in the three cold oceans that border Canada.

"Given the condition of the sea water that surrounds Canada, once you put a diver in the water, he really can, depending on the temperature of the water, only be effective for so long," said Thompson.

"It's all about stealth and extending the time you can leave a guy submerged — and by submerged, I mean hidden, depending on what the mission set is."

In Canada, the ultra-secret special-forces commandos known as Joint Task Force 2 have been paying particular attention to the country's coastlines.

Last year, it was revealed JTF-2 had turned to the private sector for help in early warning of possible terror threats coming from the sea. The organization tapped into an existing fisheries surveillance contract with Provincial Airlines Ltd., a subsidiary of Provincial Aerospace Ltd. of St. John’s, N.L., to monitor the movements of vessels of interest off the country's coastline.

At a rare public appearance last summer during the military's annual northern exercise, JTF-2 commandos stormed a mock "vessel of interest" at sea while the prime minister, the defence minister and the media looked on.

The subs aren't cheap: each one — some of them currently operate as underwater tour boats with up to 20 available seats — carries a price tag of $5 million.

Sea Urchin Submersibles and Nuytco Research Ltd., a subsidiary of Can-Dive Construction Ltd., are the two other Vancouver companies with underwater technology that has caught the attention of the special forces community.

Nuytco offers one-man and two-man deep sea diving suits. Can-Dive markets small diesel-electric submarines, but does not build them.

Over the last 40 years, Vancouver has become a centre of excellence in deep-diving research and technology, said a May 4, 2011 briefing note prepared for Thompson.

International Submarine has also made a name for itself in the field of remotely operated and autonomous underwater vehicles, which many in the naval community believe is a revolution in the making, similar to unmanned aerial vehicles.

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