A small device exploded near a busy train station in central Bangkok on Tuesday afternoon, police said, a day after a powerful bomb killed 20 at a religious shrine.

"No one was killed or injured. Police are at the scene to investigate what kind of device it was," an officer at Yanawa police station, who asked not to be named, told AFP.

He said the incident took place shortly after 1pm (0600 GMT) near the Saphan Taksin BTS skytrain station.