Ronnagorn Gunphai, 17, was attacked at the entrance to the school by a gang of six teenagers, one of whom stabbed him just beneath the ribs on the right side of his body, in the area of his liver.
The Kusoldharm Rescue Foundation were alerted by a school teacher at around 2:30 pm. At the scene they found a crowd of students, plainly upset and frightened by what they had just witnessed.
After first aid, Ronnagorn was taken to Thalang Hospital for treatment. His injuries are understood not to be life-threatening.
Police said a friend of Ronnagorn’s told them it all happened very fast. Six teenagers rode up to Ronnagorn on motorbikes and stabbed him, before fleeing.
Police believe the attack was part of a teenage gang war, and that Ronnagorn knows who his attackers are. They were due to question him in hospital yesterday.
Investigators added that there had been trouble between the two groups before.