Naga fireballs (; ), also known as Mekong lights, and "bung fai paya nak" by the locals, is a phenomenon said to be often seen on the Mekong River. Glowing balls are alleged to naturally rise from the water high into the air. The balls are said to be reddish and to range in 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 fireballs reported varies between tens and thousands per night.

Naga fireballs (; ), also known as Mekong lights, and "bung fai paya nak" by the locals, is a phenomenon said to be often seen on the Mekong River. Glowing balls are alleged to naturally rise from the water high into the air. The balls are said to be reddish and to range in 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 fireballs reported varies between tens and thousands per night.