1.   Britain, the only other country whose submarines regularly prowl the Barents, has denied having a submarine in the area at the time.

2.   For decades the top of the world was off limits to much civilian inquiry because nuclear-armed American and Soviet submarines prowled and tangled beneath the ice.

3.   Japanese submarines prowl San Bernadino and Surigao straits.

4.   On a December night during World War II, a British submarine prowled the waters off the Italian-occupied Greek island of Cephalonia.

5.   For decades, the Arctic Ocean was off limits to civilians as Soviet and American nuclear submarines prowled the area.