The counter-coup rumour circulating in social media has been linked to a person who runs a foreign-registered website, national police chief Somyot Poompunmuang says.
"We know who he is and where he lives," Pol Gen Somyot said, although he declined to give details beyond saying the rumour came from a person who owns the website www.dangdd.com, registered abroad.
Public records show the site is registered to Dr Richard Saisomorn, of a group called AmeriLao in the US state of Oklahoma.
The website owner is believed to have spread the rumour of a counter-coup against Prime Minister Prayut Chan-o-cha, who heads the National Council for Peace and Order that toppled the Yingluck Shinawatra government, following months of political gridlock.
The counter-coup rumour circulated quickly online. Those behind it cited a recent order from the 2nd Army to units under its supervision not to move weapons and soldiers unless they get permission from Gen Prayut.
Pol Gen Somyot also kept a tight lip on whether the Thai-language website was connected to a political group in the country, although the site itself makes no reference to political parties. Its banner proclaims the motto, "Freedom means the supremacy of human rights everywhere" and there are no references to Thailand at all.
Police have blocked access to the forum-styled website which operates on a web server abroad.
The authorities have the technology that allows them to block access to websites after they are opened.
However, the web owner can re-open them quickly after making a minor change to the domain name, Pol Gen Somyot said.
"By making a minor change to the domain name, such as by adding a period or other symbol, they can re-open the website and allow comments or content to be posted," he said.
The national police chief suggested security agencies consider installing a single gateway system which can better prevent content deemed inappropriate from being put up on websites including those overseas.
Though the technology costs up to one billion baht to install, the investment would be worth it for the sake of improved national security, Pol Gen Somyot said.
Gen Prayut yesterday downplayed the counter-coup rumour and repeatedly dismissed the accusation that he wants to prolong his power in office.
"Let them do it [any element wanting to engineer a counter-coup] and we will see what happens," he said while presiding over an international conference on anti-corruption.
Gen Prayut said the military does not want to remain in power for too long.