Parit Ratanakulserirengrit, a nephew of Luang Seriruangrit, went to Dusit Police Station yesterday afternoon to lodge a complaint and notify police the plaque is missing.

Seriruangrit was among 115 members of Khana Ratsadon (People’s Party) that staged the revolution to turn Thailand, then known as Siam, from an absolute monarchy to a constitutional monarchy in 1932.

Some members of the party as well as their heirs and relatives are concerned over the missing plaque, which marked the change of the country’s government, Parit told reporters.

“Many of them are senior and some of their heirs also served the country as military, police and other civil servants,” he said. “They might not be comfortable to say something about this. Therefore a younger-generation person like me has to come out to speak for them.

“I want to know how it went missing and where it is now.”

As a junior classmate of former prime minister Abhisit Vejjajiva at Sathi Chulalongkorn School and Oxford University, Parit urged the ex-premier and leader of the Democrat Party to speak out about the case.

“The plaque does not belong to any particular individual but to all Thai people,” he said.

Three students from Chulalongkorn, Kasetsart and Ramkhamhaeng universities joined Parit in lodging the complaint with police.

Police Captain Mo Rana took the complaint since the plaque was deemed state property and said he would report the matter to his superior for it to be investigated.

Historians and pro-democracy activists cried foul after the plaque, called “Mhud Khana Ratsadon” in Thai, was replaced by a new one, which makes no reference to the Siamese |revolution.

The original plaque, which had been fixed on the grounds of Royal Plaza where the leader Phraya Phahol Phonphayuhasena read out the first statement to end the absolute monarchy regime, said: “At dawn on June 24, 1932, the People’s Party on this spot gave birth to the constitution for national prosperity.” It was also called the Constitution Plaque.

The new plaque, first observed missing on Friday, reads: “It is good to worship the Buddhist trinity, the state, one’s own family, and to be faithful to one’s monarch and allow oneself to be the engine that brings prosperity to the state.”

In a statement, the Thai Academic Network for Civil Rights urged all relevant agencies and Prime Minister Prayut Chan-o-cha and the chief of National Legislative Assembly to prosecute those who switched the plaque.

“The change of the plaque showed disrespect to our ancestors who established democracy,” it said.

The new plaque reflects nothing about the constitution and also |contradicts the basic principles |in the charter as it calls on Thais to worship only to the Buddhist trinity and thus discriminates against other religions, the group said.

Some royalists yesterday praised the removal of the Constitution Plaque, saying in social media posts that it was a symbol of half-baked political change in the Kingdom.