Operator	Baba Shoji
Classification	Cargo ship
Gross tonnage	5,065 tons
Speed
Departure point	Batavia, Java Is.
Departure date	16 September 1944
Destination	Padang, Sumatra Is.
No. of POWs	approx.2,200 (14 US, 1,700 Dutch, 506 Ambones and Manadonese; 4,320 Javanese Romusha
Location of disaster	Off Moaca Moaca Point, Sumatera Island
Date of disaster	18 September 1944
POW casualties	1,520 & 4,120 Javanese Romusha
POW survivors	880 (of a total of approx. 6,520 aboard)
Painting	Courtesy of Mr. Kihachiro Ueda

On 16 September 1944, Junyo Maru left Batavia harbor escorted by two small gun-boats. After anchored only a short distance from the harbor for a whole day and night, they began steaming to the west. On the following morning, they passed through Sunda Strait into the Indian Ocean. Then they turned to northwest and were sailing some distance off along the Sumatran coast, headed for Padang. At around 17:30 on 18th September, there was a dull thud, and the ship shook. Men in the holds jumped and climbed up the ladders to the top side. A few seconds later, there was another louder bang. The ship shook much more violently, and smoke began coming into the after hold. All of those were caused by the attacks of the British submarine HMS Tradewind.

Aboard Junyo Maru was in chaos. Every crewmember was shouting, "Torpedoed! Abandon ship!" and the people made a scramble to jump into the water. The stern of Junyo Maru went down deep into the sea with her bow rising in the air. However, hundreds of people were still clinging to the side and deck. Junyo Maru took a sudden big list, and two big holes could be seen, one below the foremast, and another at the stern. On the raised bow, Romusha lay on top of another in a heap. Some climbed up the mast, as though it would save them. As the ship stood steeper, they trembled down the deck, and fell into the water. Junyo Maru stood almost upright, and disappeared under the surface of the sea against the red sunset sky.

Of the approx. 2,220 allied and Indonesian POWs 1,520 were killed or drowned. Of the 4,320 Javanese Romusha, 4,120 were also perished. The loss of 5,640 human lives was the worst record in any single shipwreck in the Pacific.

The 880 survivors were taken to Padang, and worked to build the Sumatra Railroad. When the war was over, they say that only 96 POWs survived.