The video clip was posted in the social media and went viral prompting a stream of criticisms.
Pol Maj-Gen Somchai Kaosamran, commander of Highways Police Command, said Thursday he knew the identity of the patrolman in question but declined to name his name until the charge against the suspect can be verified. He expected the result of the probe within seven days.
The commander assured that both the suspect and the victim would be fairly treated and the culprit would be punished.
The incident took place on the Asian highway in Nakhon Sawan province.