The photograph showed two teenagers on a motorcycle placing a bomb at a Bangkok Bank ATM booth in front of Somdet Phraborom Rachineenat Hospital in Na Thawi district.
Police were tracking the suspected group and their motorcycles as in the explosions at three ATM booths in three districts of Songkhla, the suspected bombers were two teenagers on motorcycles.
Songkhla provincial police commanders will meet this afternoon to conclude the cases and seek arrest warrants from the court.
Lt Gen Sakon Chuentrakul, Fourth Army Region Commander, earlier said that the assailants targetted damaging the economy in the southernmost province.
He said the Internal Security Operations Command would do its best to protect local residents and applied offensive operation to tackle those who violate the law.