NEW DELHI (AP) — Despite hours of searching the dark, muddy water inside a submarine crippled by twin explosions, Indian navy divers have yet to find the 18 sailors feared dead there, possibly because the heat of the blasts melted some hatches shut, the navy said Thursday. The explosions in the submarine's torpedo compartment sent nearby sailors jumping into the sea in panic and left the diesel-powered vessel partially submerged at a dock, with a portion visible above the waterline. "There would have been signs of life through tapping of the hull by the sailors, which is a known procedure for the rescue of sunken submarines," he said. Because the submarine was docked, navy watchmen were on the submarine rather than the normal crew, Admiral D.K.