Tamil Tigers Large Submarine

[World B4]

H I Sutton has made a comprehensive report on the various submersibles used by the Sea Tigers on his quite frankly amazing website. They began construction of a large submarine, either for attack or smuggling, but left it unfinished. It's main distinguishing characteristic is that it's somewhat square shaped on one end. Is there any speculative art, or better yet but very unlikely, any recovered designs of what the sub would have looked like if it were to be completed?