The navy sank nine Tamil separatist vessels Wednesday in a fierce battle off Sri Lanka's northwest coast that killed 40 rebels and one naval officer, the military said. One navy craft sank, the rebels said, according to AP. Separately Wednesday, ground battles in the north left 26 guerrillas and two soldiers dead, the military said. The sea clash erupted early Wednesday after naval patrol boats attacked a rebel flotilla transporting weapons off northern Mannar district, said the military's spokesman, Brig. Udaya Nanayakkara. Backed by helicopter gunships, the navy sank nine of the 16 rebel boats, killing 40 guerrillas, Nanayakkara said. «One navy craft was also severely damaged as two suicide boats rammed into it,» he said adding, at least one navy officer died and 10 sailors were missing. The rebels said their fighters sank one naval craft and damaged two others in the three-hour clash, according to an e-mailed statement from rebel spokesman Rasiah Ilanthirayan. Four Black Tigers, the rebel group's suicide fighters, died in the attacks, it said.