They are alleged gang leader A-tid Saengprasert, Tanong Boonket and the 17-year-old boy.
They allegedly used a gas-welding machine to extract the cash from the Siam Commercial Bank ATM on Sukhumvit Road’s inbound lane towards Sattahip district last week.
A-tid confessed that he had attempted to rob ATMs four times before in Bangkok but had failed until last week’s heist, Chon Buri police chief Maj-General Khatcha Thatsat told a press conference.
Police are trying to retrieve the cash and are looking for the gas-welding machine and gas cylinder in Bang Pakong River, where the suspects claimed to dump the evidence.