A video put together by Daily News showed an explosion and resulting fire at the Miniso shop on the third floor of Siam Square One in the early hours of yesterday morning.
A man in a surgical mask and hat carrying a shoulder bag was caught on CCTV suspiciously moving about the store on Thursday.
He was believed to have cut open a stuffed toy and placed a device inside it and put it back on the display stand.
The shop was seen closed later on Friday with a notice on the front door.
The incident is believed to be part of several bombing incidents and fires in the capital on Friday.