Two homemade bombs were found in Pak Kret, northwest of Bangkok, on Sunday but police are linking them to vocational students.
The two “ping-pong” bombs were found at around 2pm in front of a 7-Eleven shop on Tiwanon Road in Nonthaburi province.
Police said they thought that the homemade bombs were made by vocational students for use against their rivals.
Quoting a food vendor, Pak Kret police said the bombs were possibly brought to the scene and hidden by a group of five teenage men who reportedly went to the convenience store on three motorcycles.
The food vendor said two groups were involved in a chase on motorcycles. A loud bang was heard and a used ping pong bomb was later found in the area.