The SS Ourang Medan was a Dutch cargo ship that sent out a distress call, but by the time help arrived the entire crew were dead with their eyes open, staring ahead with a look of incredible horror on their faces. As she was about to be towed to land the ship exploded, and sank to a watery grave refusing to give up any answers as to what happened on her salty decks.

The first mention of the SS Ourang Medan and all its suddenly dead crew was in a periodical published by the United States Coast Guard. Allegedly, the ship sent out a distress call, it went something like this:

"All officers including captain are dead lying in chartroom and bridge. Possibly whole crew dead." This message was followed by indecipherable Morse code then [the words] "I die."

Help arrived as you can imagine and only after a few hours. It was too late. Everybody on board was dead. As the rescue party boarded they saw a gruesome sight the entire crew was at the doorway of decomposition with their eyes open, their arms outstretched, and their lifeless faces twisted in absolute horror. The ships dog was dead as well found with a tooth-filled snarl on its lips.

The Medan itself was completely undamaged, and the sailors had no visible wounds to explain their mass-demise. Before the boat could be explored further flames exploded out of the cargo hold, and the would-be rescuers were forced back to their own vessel. Then the death-ship exploded, and sank out of mans reach. Had the other ships crew not managed to cut the ropes holding the two barges together, perhaps both would have plunged together.

There are several theories as to how all those men died ranging from the inhalation of carbon monoxide to some kind of nefarious UFO intervention. In the end, nobody really knows what happened.

You know what else nobody knows? If the Ourang Medan ever concretely existed or not. As we already stated, the first mention of the Medan was in a publication put out by the US National Coast Guard. One would think that meant sources were well documented. But perhaps this isnt the case. Wikipedia seems to think so anyway:

Several authors note their inability to find any mention of the case in Lloyds Shipping Register. Furthermore, no registration records for a ship by the name of Ourang Medan could be located in various countries, including the Netherlands. While Bainton states that the identity of the Silver Star, which was reported to have been involved in the failed rescue attempt, has been established with some certainty, the lack of information on the sunken ship itself has given rise to suspicion about the origins and credibility of the account. Bainton and others have put forward the possibility that accounts of, among others, the date, location, names of the ships involved, and circumstances of the accident might have been inaccurate or exaggerated, or that the story might be completely fictitious.

So did the ship ever exist? No record of it anywhere would certainly seem to indicate that it didnt. This point is counter-argued with a barely-post WWII mentality saying that some sort of top secret chemical cargo may have required absolute secrecy and then triggered all those deaths.

More at http://theunexplainedmysteries.com/SS-Ourang-Medan-Ghost-Ship.html