An unarmed U.S. cruise missile was launched from a B-52 bomber over the Beaufort Sea on Wednesday and streaked 1,500 miles on a test flight across frozen northwest Canada.
The test was held to evaluate the 20-foot-long missile's ability to hug terrain similar to that of Siberia and the ability of Canadian jet fighters to intercept incoming Soviet missiles.
The low-altitude missile, capable of carrying nuclear warheads, flew south along the Mackenzie River, turned east over northeastern British Columbia and headed for Cold Lake, Alberta, where it landed on schedule by parachute at 2:47 p.m., about 4 1/2 hours after launch.
The missile will be flown to the United States for evaluation. U.S. and Canadian officials refused to discuss the performance of the missile or the interceptor aircraft for security reasons.
The test, one of several permitted under a U.S.-Canadian defense pact, prompted a protest by about a dozen peace activists outside the Canadian Forces air base at Cold Lake, about 150 miles northeast of Edmonton.
Royal Canadian Mounted Police arrested four demonstrators for refusing to remove a banner stretched across the base entrance. All four were charged with obstructing police.
The Greenpeace environmental group sought to disrupt the morning shift change at the base by blocking the front gate. Base workers, however, came to work early, and the protest had little effect.
The test provoked few other protests in Canada.
Opponents of the cruise missile believe the weapons could upset the nuclear arms balance because their small size and ability to fly under enemy radar make them difficult to detect.
Under the five-year U.S.-Canadian defense pact, the United States is permitted to conduct six cruise tests a year in northern Canada. Wednesday's test was the first of four planned this winter.
Another test is scheduled for Friday.