FAT have decided to backtrack on earlier statements of the incident's significance and launch a formal investigation
The rivals met in the semi-final fixture with Buriram coming out 1-0 victors. But Muangthong supporters who had been taunted by Buriram fans during the game sought out retribution at the final whistle and rushed in to assault the home fans, knocking down a security personnel in the process.
The exact number of casualties is not yet known with most parties hesitant to be drawn into an official investigation.
Somsak Onsmaa, Thai Premier League’s (TPL) Vice President said: “We’ll have some heavily punnishment if it happened in the TPL. But I have to admit that anything that happens in other competitions are beyond our reach. Everything’s up to FAT for this incident.”
Ong-art Korsinkha, FAT Secretary and the President of TPL contradicted his deputy's response however, adding: "We’ll proceed on this as fast as possible. For the punishment, FA Cup’s regulations are no different from TPL’s regulations anyway so it can be used here too.”
Korsinkha, soon backtracked days later as he brushed aside the incident as insignificant.
"I asked for a report about this from the Match Commissioner but nothing came in," he said.
"And from what I've been told by our officers, it's nothing lethal. Staff can handle it well. Nothing gone terrible. So no punishment."
FAT have since decided to launch investigations however as footage of the incident as shot by Goal Thailand went viral.