Military officials and experts believe that if a North Korean torpedo was involved in the sinking of the South Korean Navy corvette Cheonan, it was probably launched from a 325-ton Shark-class submarine. The sub ranks between a full-blown submarine and a mini-sub in terms of size. South Korean military intelligence are reportedly focusing on the fact that one or two Shark-class submarines from a submarine base in Cape Bipagot, South Hwanghae Province are unaccounted for during the time of the Cheonan's sinking. The Bipagot submarine base is around 80 km from Baeknyeong Island. Shark-class submarines can travel at speeds of...