Phaya Nak (; ; "phaya" derived from Mon which mean "high nobility") or Nakkharat (; ) in Thai beliefs, Nāgas are considered the patronage of water. Nāgas are believed to live in either water bodies or in caves. According to a popular legend, the Mekong River in northeastern Thailand and Laos was said to be created by two nāga kings slithering through the area, thus creating the Mekong and the nearby Nan River. The Mekong is synonymous with the unexplained fireballs phenomenon which has long been believed to be created by the nāgas that dwell in the river.