Police are preparing to take legal action against the organisers of a political rally on the Skywalk at Pathumwan intersection on Saturday for not obtaining permission required to stage a public gathering.
Pol Maj Gen Methi Rakphan, commander of Metropolitan Police Division 6, said on Sunday the rally called by Future Forward Party (FFP) leader Thanathorn Juangroongruangkit was clearly in violation of the public gatherings law.
He said the organisers failed to secure permission or declare the purpose of the event, noting that police are also looking into the conduct of the rally leaders.
"It is clear the rally was unlawful because no permission was obtained. There are regulations that need to be followed," he said.
Though police maintained that no permission was granted for the rally, they did not intervene in the relatively brief event, attended by hundreds of people, which wrapped up around 6pm without incident.
The rally was called by Mr Thanathorn after the Election Commission (EC) decided to ask the Constitutional Court to consider disbanding his party for allegedly violating the organic law on parties for accepting a 191-million-baht loan from him to finance its election campaign.
Pol Col Kissana Phathanacharoen, spokesman for the Royal Thai Police, said on Sunday police and security authorities were sent to observe the rally and are examining evidence to determine if any laws were broken.
He also pointed out the 2015 law on public assemblies permission exists so police can make proper preparations to ensure peaceful and orderly gatherings.
FFP spokeswoman Pannika Wanich said on Sunday the rally was not unlawful and it was an expression of the people's civil rights under the coup-sponsored charter.
She said the people came out to voice their dissent against injustice and the government's handling of national affairs.
Ms Pannika also hinted the FFP was planning more activities when asked to clarify if Mr Thanathorn was referring to the "Wing Lai Lung" (Run to Oust Uncle, a reference to the prime minister) running event, when he told rally participants that he would be seeing them next month.
"Mr Thanathorn has already announced he will join the run. For the FFP's [other] activities, you'll have to wait and see," she said.
Speaking at a forum in Chanthaburi, FFP secretary-general Piyabutr Saengkanokkul said the party faces disbandment because those in power want to break it up and acquire its MPs.
He pledged to carry out political activities outside parliament if the FFP ends up being dissolved and he ends up losing his MP status. He said the party should turn the crisis into an opportunity.
"If they won't let me work in parliament, I will do it outside," he said.
Tanawat Wongchai, a former president of the Chulalongkorn University Student Council, said the Jan 12 run has been organised by the Student Union of Thailand to drum up public support for the ouster of Prime Minister Prayut Chan-o-cha.
He also criticised the public gathering law, accusing it of being a tool to curb free speech and civil rights, and adding that it will be rendered useless if large numbers of people join street protests.
Government spokeswoman Narumon Pinyosinwat told the media on Sunday that people should do their research before joining a street protest.
Asked about Saturday's rally, Ms Narumon said the prime minister was concerned about public safety and would rather see dissent toward the government addressed by MPs in parliament.
However, anti-regime activist Nuttaa Mahattana hailed Saturday's rally as a success, saying a "Prayut, Get Out" campaign should be launched simultaneously with the charter amendment bid.
Ms Nuttaa warned the FFP not to lose sight of the campaign or exploit for the situation for its own gain, otherwise it could turn off possible allies who do not share the party's political stance.
Meanwhile, in Chiang Mai, Pol Maj Chuwaphon Chaisorn, inspector at Chiang Mai police station, lodged a complaint with local police against activists who opened a Facebook page named "Liberal Assembly of Chiang Mai University for Democracy" which invited people to join them at Tha Pae Gate in Chiang Mai's Muang district on Saturday, the same day of the gathering in Bangkok.
He accused them of organising an unlawful assembly.