The Predator B drone, the first unmanned aircraft to patrol the northern U.S. border, is followed by a chase plane as it lands at the Grand Forks, N.D., air force base in December 2008. ((John Stennes/Herald/Associated Press))

The U.S. Department of Homeland Security launched another unmanned surveillance aircraft over the Canadian border on Monday, this time in the Great Lakes area, to try to stem the flow of drugs, migrants and terrorists into the country, U.S. officials told CBC News.

The U.S. has been using the Predator B drone aircraft to patrol its border with Mexico.

"It [has] been very successful in using that technology there, and we're testing to see if we can apply that technology to the northern border as well," said Steve Sapp of U.S. Customs and Border Patrol in Fort Drum, N.Y., which is the plane's base.

The first unmanned surveillance began over the Manitoba portion of Canada's border with the U.S. in February with a $10-million plane based at a military facility in Grand Forks, N.D.

The Predator is the unarmed version of the drone plane that the U.S. uses to conduct air strikes in Pakistan, Iraq and Afghanistan. The aircraft is able to fly at an altitude of 6,000 metres and can remain in the air for 20 hours.

The plane is equipped with sensors and cameras capable of detecting a moving person from 10 kilometres away.

The planes will gather information along the border and transmit it to operators who will in turn contact border agents. The drones will not carry weapons and the U.S. will need permission to send them into in Canadian airspace.

In eastern Canada, the focus of the Predator is the Akwesasne Mohawk Territory, which straddles the St. Lawrence River near Cornwall, Ont., and sprawls across the border of New York state.

"Essentially, we're supplying high-grade marijuana through this one small rural county of 50,000 people, thanks to the border, to all of the northeast," said Derek Champagne, district attorney of Franklin County, N.Y., and head of the area's border and narcotics task force.

However, people on the reserve are uneasy about being watched, Mohawk youth counsellor Brant Davis said.

"We no longer have the life we had 20 years ago here. Cameras, infrared, laser, informants, everything."

The border with British Columbia may be the next location the Predator visits after the trial wraps up this Thursday.

If the tests are successful, the surveillance will become permanent, Homeland Security says.