The Sri Lankan separatist Tamil Tiger movement is using Canada as a restaging base, a think-tank professor in Singapore told the Canadian Broadcasting Corp.

Professor Rohan Gunaratna, head of the International Center for Political Violence and Terrorism Research, told the CBC all indications point to the group using Canada as a base to renew their independence bid.

"I cannot think of any other country that is more important for the Tamil Tigers as Canada, to regroup and continue their campaign against Sri Lanka," Gunaratna said.

The group is designated as a terrorist organization by Canada. Its rebels waged a bloody 23-year insurgency for independence, but was defeated in May by Sri Lankan government forces.

Gunaratna's comments came after 75 Tamil immigrants were taken into custody from a ship docking in British Columbia Oct. 17.

Immigration Minister Jason Kenney said there was concern the men seeking refugee status had questionable histories.

"It's our view (the migrants) constitute a flight risk and we are not entirely satisfied about their backgrounds," Kenney said.