WINNIPEG, Manitoba (AP) - Unmanned surveillance aircraft will start patrolling the Canadian border by this fall, using Grand Forks, N.D., as the takeoff point, a border patrol official says.

Scott Baker recently took over in Grand Forks as chief patrol agent of Customs and Border Protection, an arm of the Department of Homeland Security. He will be responsible for guarding the 850-mile stretch of border between Lake Superior and Montana.

Baker said the propeller-driven drones called Predators will be launched into American airspace by September, and will fly day and night.

"Just one of the wrong people getting through, driving through our border area, could spell catastrophe," Baker said. "So, it is a concern."

Doug Marshall, the director of project development at the University of North Dakota's aerospace school, said monitoring the border by drone is more efficient than any effort involving humans.

"We don't have hordes of Canadians sneaking across the border to come shopping in Grand Forks," Marshall said.

At first one drone, with more to follow, will patrol much of the 5,430-mile frontier Canada and the United States share between the Atlantic and Pacific oceans. Predators, known by the military as unmanned aerial vehicles, have flown missions along the U.S.-Mexico border for several years, Baker said.

A Predator can cover about 850 miles in a five-hour mission and can remain airborne for up to 36 hours. Depending on lighting conditions and weather, its cameras can detect a person on the ground and identify movements, but the drone is not accurate enough to show facial features.

The U.S. Customs and Border Protection agency in North Dakota also will get 22 pilots to fly manned missions in airplanes and helicopters, a deployment similar to others in Bellingham, Wash., Great Falls, Mont. and Plattsburgh, N.Y.

Baker said Grand Forks was chosen as a Predator hub in part because of its location.

"We're dead center on the northern border," he explained. "So, they can go either way and they're equidistant."

Ordinary Canadians might be taken aback by the use of the Predators to track cross-border traffic, one Canadian defense analyst believes.

"Didn't we have the longest undefended border for a very, very long time?" asked Ian Glenn, chairman of ING Engineering, an Ottawa consulting firm. However, he acknowledged the machines will likely be productive.

"Will it be a deterrent to terrorist activity? Yes, I guess," he said.

Sen. Byron Dorgan, D-N.D., said Friday that officials from the federal Department of Homeland Security will visit Bismarck, Fargo and Grand Forks next week to meet with state and National Guard officials about the new Northern Border Air Wing branch in Grand Forks.

Dorgan said in a statement that the trip will be led by Michael Kostelnik, a Customs and Border Patrol official responsible for air and marine activities.