The fireballs spectacle, which has left scientists scratching their heads in disbelief, occurs around the full moon of the 11th month of the lunar year, or at the end of Buddhist Lent.
According to local legend, the fireballs are discharged by a Naga, a mythical serpent in the Mekong River, to celebrate the return of the Lord Buddha from heaven at the end of Buddhist Lent.
According to an unofficial report on FM 90.5 MHz radio station, altogether 67 Naga fireballs were counted in the sky this year. The first one was witnessed in Ratana Wapi sub-district around 6.10pm. Observers at Wat Tai in Phon Phisai municipality found the event extremely disappointing this year because not a single fireball was disgorged from that part of the river.
Ratana Wapi sub-district this year saw 43 Naga fireballs, the highest number, followed by Phon Phisai (16), Sangkhom (5) and Tha Bo (3). Last year, a total of 301 fireballs were observed.
More than 20,000 visitors, both local and foreign, also flocked to Khong Chiam district of Ubon Ratchathani to get a closer glimpse of the mysterious spectacle, where 27 flares were seen.