Three crewmembers found dead on a South Korean freighter that washed ashore in Shimane Prefecture on Sunday may have died after inhaling toxic gas generated from rotten squid organs, local Japan Coast Guard (JCG) officials said.  Three crewmembers were found dead in two storage rooms of the freighter and its skipper was unconscious in one of the rooms.  JCG officers found rotten internal squid organs in storage rooms where the three men were found dead.  Investigators suspect that the three crewmembers died from either an oxygen shortage or inhalation of carbon monoxide that had been generated from the rotten squid organs. The coast guard office said carbon monoxide and hydrogen sulphide were detected in the cabin.