Pol Col Anant Harikchan, the Chawang district police chief, said the incident occurred at about 10.30pm in front of a stage where a large number of people, mostly teenagers, were dancing to the music.
A clash between two groups of revellers broke out at the time. While police were racing to the scene, a glass bottle with a ping pong bomb inside was thrown into the crowd and exploded.
Six men, aged from 18 to 30, were wounded in the blast. Two of them, Ampon Chaiwararom and Sompong Buakaew, sustained deep wounds to their eyes from broken pieces of glass. They were admitted to Nakhon Si Thammarat Hospital.