The large 392.5-feet long IJN auxiliary transport vessel Seiko Maru was launched on 14 May 1940 as Japan readied itself for war in the Pacific. She had her machinery, engine and boiler rooms at the stern – so she resembled a tanker or oiler.
On 17 February 1944, as Task Force 58 fast carriers launched their surprise 2-day raid codenamed Operation HAILSTONE, she was at anchor in the IJN Fourth Fleet anchorage north east of the man-made aircraft carrier shaped Eten Island. A valuable target she was quickly attacked and took bomb hits aft from USS Enterprise Douglas Dauntless dive-bombers that blew out both sides of her hull. 
She was set ablaze and settled by the stern into 52 metres of water, where she now sits upright and largely intact – barring the bomb damage aft.