It remains a mystery that never ceases to puzzle both visitors and locals alike. Just what is the origin and nature of the fireballs that fly from the surface of the Mekong River high into the night sky for all to see?. Locals swear there is absolutely no doubt at all about the origin of the fireballs. Naga, the serpent reportedly dwelling in the murky currents of this mighty river, propels fireballs skyward, probably to remind villagers to treat this life-giving river with respect.
Of course, there are detractors, researchers who have spent years of study attempting to explain away the fireball phenomenon, all to no avail.

Some say it is an elaborate hoax, but the only way to find out is to travel to Nong Khai and check out river scene and the carnivals that villagers organise to celebrate the now famous legendary serpent. Festivities run from 10 to 16 October, along the Mekong River bank, in Phon Pisai district in Nong Khai province. There are also corresponding celebrations on the Lao side of the river and no shortage of theories on whether Thailand's neighbours, on the opposite bank, may know more than they are admitting on what causes the spectacle.