The government of Canada is raising questions of public security during detention hearings for some of the 76 Sri Lankan Tamil illegal immigrants it is detaining.

That is because there are concerns the group may include those who may have links with the LTTE, a banned terrorist organization in Canada.

At least three men among them are undergoing their second and third mandatory detention hearings before an immigration and refugee board in Vancouver.

Details of the hearings are under a publication ban because they are being treated as potential refugee claimants, Canadian TV reported.

The Sri Lankans arrived on a decrepit little freighter on Canada's west coast earlier this month.