SINGAPORE - As their ship inched towards the naked man clinging to a ring buoy, Captain Cornelis Plugge and First Officer Srdan Bazdan of the Diogo Cao thought he was dead.

They were astonished when Mr John Low lifted his right arm to signal he was alive. The 60-year-old said he was astonished anyone saw him from the ship, which to him looked 10-storeys high.