The exercise, simulating a capsized boat in the strait, began as expected around 9 a.m., but a helicopter involved in the exercise was called in to help search for a man lost in the waters of the Bay of Chaleur.
The 64-year-old Montreal man, who was visiting Carleton, Quebec, waded into the bay in high fishing boots. The man's boots somehow filled with water and he was pulled under by the current.
His body was recovered at about 3 p.m.
The exercise in the Northumberland Strait continued without the helicopter.