The new plaque symbolising democracy that was installed on Sunday morning by protesters of the United Front of Thammasat and Demonstration at Sanam Luang has been removed overnight.
The plaque was embedded in cement at Sanam Luang in a ceremony led by protest leader Parit "Penguin" Chiwarak at 6.39am on Sunday to mark "a new era of the people's power" and declare "Thailand belongs to the people."
The plaque was intended to replace an old one commemorating Siam's transition from absolute monarchy to constitutional democracy in 1932. The old plaque mysteriously disappeared in 2017and was replaced by one bearing a pro-monarchist slogan.
After a ceremony to install the new plaque on Sunday, the protesters marched to an area outside the Supreme Court and handed over a petition containing their demands to the Privy Council president via Metropolitan Police Bureau chief Pol Lt Gen Pakapong Pongpetra.
Mr Parit then called off the rally and declared a new demonstration would be held outside Parliament on Thursday, the second day of a two-day debate on motions to amend the constitution.
The Bangkok Metropolitan Administration reportedly closed the Sanam Luang gates at 10pm on Sunday and opened them again on Monday at 5am. That was when the new pro-democracy plaque was found to have been removed. The spot where the plaque was planted had been covered up with cement that still looked wet.
"I’ve received a report that the plaque is gone but I don’t know how and I don’t know who did it," Bangkok’s Deputy Metropolitan Police Bureau chief Piya Tawichai told Reuters.
"Police are checking with the BMA (Bangkok Metropolitan Administration) and checking who took it out as the plaque is part of the evidence to charge the protest group (for this wrongdoing)," Pol Maj Gen Piya said.
Police and others said on Sunday the installation of the new plaque was a violation of certain laws.
When asked about the plaque's disappearance, a city employee manning an entrance gate said he knew nothing about it as he had just begun his shift.
Fine Arts Department director-general Prateep Pengtako said in an interview with Matichon newspaper that the department would file a complaint with police against the protest leaders for violating the Act on Ancient Monuments, Antiques, Objects of Art and National Museums, which he said applies to Sanam Luang.