The Naga fireballs also referred to as Mekong lights, are a phenomenon seen in the Mekong river—in Thailand and in Laos, in which glowing balls rise from the water high into the air. The balls are reddish and have diverse size from smaller sparkles up to the size of basketballs. They quickly rise up to a couple of hundred metres before disappearing. The number of fireball. ls reported varies between tens and thousands per night.
"Embedded in the folklore and Buddhist way of life is the King of the Naga, a serpent-like creature, who is reputed to reside deep beneath the Mekong River in an underwater city, the Muang Badan.
Everything in their daily lives, from house building to the running of their schools, factories and hotels is influenced by their belief in the Paya Naga and its supernatural powers.
The people of Isan and their Laos neighbours on the opposite banks of the Mekong are closely related - so too are their beliefs in the Paya Naga and the mysterious Bang fai (Naga Fireball) that appear every year from beneath the waters of the Mekong on the last day of the Buddhist lent in October.
Pra Kru Udom Phisaikanarak, the head monk of Wat Chomthong and Phon Phisai District Head monk (Cha Kana Amphoe) explained the history and legend of the Bang fai Paya Naga (Naga Fireball) - the natural and unexplained phenomenon of the fireballs coming from beneath the waters of the Mekong River...
On the last day of the Buddhist Lent the people of each village located near the river at Amphoe Phon Phi-sai floated their fire-boats as a mark of respect and tribute to the Lord Buddha.
They then placed torches made of a substance of insect waste collected from trees on their 20 - 30 meters long bamboo boats to illuminate them...In order to make their boats look more spectacular some team members fired small Bang fai (rockets) and the circular Bang fai known as Talai into the sky. It was then that a curious and so far unexplained phenomenon occurred - some Bang fai were fired as if from under the water, as if the Paya Nagas wanted to participate in the event. This was hundreds of years ago and the phenomenon has occurred every year since.
It is also said that it is not only beneath the river that the underwater town or city exists. The Muang Badan as it is known is said to run throughout the whole geographical area of Nongkhai Province - the home of the Paya Nagas (Naga Fireball's)."