Police were called to examine an exploded firebomb at the Platinum shopping centre in the Pratunam area of Bangkok on Friday, after being contacted by a shop owner six days after the bomb went off.
A police source said the improvised explosive device was connected to a power strip and had been placed in a scarf shop on the fifth floor of the centre on Phetchaburi Road in Ratchathewi district.
The newly found bomb was of the same design as seven others believed to be placed in the Pratunam and Siam Square shopping areas and linked to the Bangkok bombings on Aug 1 and 2.
The bomb was wrapped with a scarf. The owner of the shop found it late last week and, without knowing it was a bomb, pushed its switch last Saturday. That caused a brief fire but people at the shop were able to put out the flames.
The source said that the shop owner only decided to inform police of the incident on Friday morning, and officers went there to collect the object.
Authorities are hunting for more than a dozen suspects in connection with the Aug 1 and 2 attacks. On Thursday, at their first news conference since the incidents, police had little new to report, and said they believed the attacks may be linked to politics.