With the youth-led protest appearing to evolve into a bigger movement last night, the government needs to have a clear response to the protesters' demands, particularly the push for a charter rewrite, according to academics who witnessed the event.
Last night, tens of thousands of protesters packed the Sanam Luang ground to demand the charter amendment, the stepping down of Prime Minister Prayut Chan-o-cha and monarchy reform.
The protesters next plan to move from Sanam Luang to a "surprise" area.
Phichai Ratnatilaka Na Bhuket, a political scientist at the National Institute of Development Administration (Nida), said the situation could turn turn violent if the protesters moved to royally-restricted areas.
Gen Prayut is now under pressure as more people agree with demands that he resign from the office, Mr Phichai said, adding Thais are suffering from economic problems and the government has not solved them.
He said the students' call for a charter rewrite and a change of the prime minister, who has been in power since the 2014 coup and has yet to tackle economic problems, are attracting wide support from many Thais.
Phichai: PM under pressure
However, if the government pledges full support for a new charter, it can help ease the political tension, Mr Phichai said.
Commenting on former PM Thaksin Shinawatra's Facebook post, the academic said the ex-premier is trying to take advantage of the unrest to make bargains for himself.
In his post, the self-exiled former premier asked Thais about their livelihood 14 years ago before his government was overthrown in a coup led by Gen Sonthi Boonyaratglin.
When asked about a possible violent clash between pro-democracy and the authorities, Mr Phichai said the state must prevent the situation from getting out of control.
Stithorn: Govt credibility shaken
Stithorn Thananithichot, director of the King Prajadhipok's Institute, said the government's credibility is shaken from the protest.
Somjai Phagaphasvivat, a political scientist at Thammasat University, said it remains to be seen if the protesters will raise the stakes further with their demand for monarchy reform.
If protesters disperse today without offending the institution, Senate may try to stall the current charter amendment process, Mr Somjai said.
Stithorn Thananithichot, director of the office of Innovation for Democracy at King Prajadhipok's Institute, said if protest leaders spoke out against the monarchy on stage, the government would find itself in a "very difficult situation".
The political crisis could lead to the resignation of the current government and the formation of a "caretaker" government.
Wanwichit Boonprong, a lecturer at the political science faculty of Rangsit University, said the rally yesterday marks the beginning of a test of the student protest leaders' crowd management skill.
He said student activists lacked unity and do not appear to share the same beliefs.
While some touch on monarchy reform, other groups focus on other demands, the academic said, adding if demonstrators set their goals only to achieve a House dissolution or charter rewrite, they stand a good chance of winning.
"I think a major rally is coming next month and from the current economic and political situation, the movement is likely to win more allies," Mr Wanwichit said.
He noted that a violent confrontation with the authorities is unlikely unless demonstrators encroach in off-limit areas such as Dusit Plaza. And if protesters forced their way into restricted zones, it would affect the next protest, the lecturer said.
Senator Wanchai Sornsiri said the protest is a gathering of people with various demands and the government needs to address these issues as soon as possible before the protest spirals out of control.
Mr Wanchai said a protracted protest is counter-productive and the best approach to ease tension is to amending the charter.
He warned against calling for monarchy reform.
"If all the demands are rejected, I don't think it will end. They may go to Government House or somewhere else," he said.
"The situation may get out of hand and lead to something else.
"We may see a House dissolution, the government resigning or even a coup. It's all possible," the senator added.
