The incident occurred in the middle of the day when a car suddenly exploded outside a restaurant near the police station and a shopping centre, damaging many vehicles and houses nearby.
According to witnesses, the blast sent plumes of black smoke streaming into the sky and police had to blockade the entire area.
Local authorities suspected the car was stolen by Muslim insurgents during an attack earlier in the day.
Last week, the US Embassy in Bangkok warned of a possible attack by the self-claimed Islamic State (IS) in the country. Security has been strengthened across the country after the warning.
