An aerial photograph that appears to show a gigantic snake swimming along the remote waterway has emerged, sparking great concern among local communities.
But it is not clear whether the photograph is genuine, or a clever piece of photo-editing. Some suggested the 'snake' was in fact a log or a speed boat and others complained the colour of the river in the photo was too dark.
The most common theory is that the photo has been manipulated on a computer.
The image has even stumped the New Straits Times newspaper in Kuala Lumpur, which suggested readers decide for themselves.
However, on the banks of the river, villagers are convinced of the massive serpent's existence and have even given it a name, Nabau, after an ancient sea serpent which can transform itself into the shapes of different animals.