OTTAWA - If the Harper government has its way Canada's spy agency could soon have the power to derail terrorist plots -- not just gather and analyze information.

Legislation tabled yesterday would allow the Canadian Security Intelligence Service to thwart a suspected extremist's travel plans, disrupt bank transactions and covertly meddle with jihadist websites.

It would also make it easier for police to obtain a peace bond to restrict the movements of a suspect, and it extends the period for preventative arrest and detention.

In addition, the legislation would expand the no-fly regime to cover those travelling by air to take part in terrorist activities, whereas currently there must be an immediate risk to the plane.

The new plan flows from a review of fatal attacks on two Canadian soldiers last October.

The Conservatives argue the new powers are needed to help keep Canadians safe in an increasingly dangerous world.

Initial reaction from opposition parties has been cautious, while privacy and civil rights advocates are expressing fears about trampled rights and inadequate oversight.