The anti-government rally at Thammasat University on Monday night is thought to have risked offending the monarchy, sparking fears that it could trigger violent confrontations between the royalist movement and its opponents.
Comments made by protesters at the university's Rangsit Campus in Pathum Thani have potentially violated Section 112 of the Criminal Code, also known as the lese majeste law. Students announced a set of 10 demands which included changes in the country's highest institution, including Section 112 and royal prerogatives.
Prime Minister Prayut Chan-o-cha on Tuesday said that the government had been closely monitoring the situation and admitted he was worried about it. However, he refused to comment on the protesters' demands.
Meanwhile, Thammasat University on Tuesday issued a statement distancing itself from the rally and apologised for the rally that took place on its campus.
The university said that the organisers had asked for permission to hold the rally to push for their three original demands: constitutional amendments, the dissolution of the House and an end to the intimidation of critics of the government.
However, the university said that during the rally the protesters had acted and spoken beyond permitted bounds, particularly on issues which were delicate and sensitive to the feelings of the public at large.
Such actions which went beyond permitted limits were the personal responsibility of the protesters, the statement continued, since the rally organisers had struck an agreement with police officers beforehand.
Police will take legal action against all involved, particularly those who are not Thammasat University students. The university says it is willing to cooperate and ensure justice for all sides.
For the university's students who acted improperly during the rally, Thammasat will itself take action based on facts and in line with its regulations.
The university has also pledged to prevent a recurrence of Monday's incidents, saying from now it will ban political activities on its premises that risk violating the law.
Prinya Thaewanarumitkul, deputy rector of Thammasat University, apologised on Tuesday for comments made by people during the rally.
He said the organisers had failed to adhere to the agenda agreed upon when they sought and obtained permission for the demonstration on the university campus.
Senator Kamnoon Sidhisamarn told parliament that the demands made by protesters during the rally were unprecedented and their comments were the most violent he'd ever heard.
Their demands went far beyond the calls for the government to be ousted or for charter amendments, he said.
"I believe both the lower and upper chambers of the parliament agree that the actions of some protesters during the rally went beyond the proper limits," Mr Kamnoon said. "This risks triggering the repeat of the Oct 6, 1976 incident, which caused a deep wound that would be passed on to future generations. Parliament should serve as a forum to find a solution before the Oct 6, 1976 incident repeats itself."
On Oct 6, 1976, soldiers, police and members of far-right groups surrounded the Thammasat University campus in Tha Prachan and killed scores of student activists who had gathered to oppose the return of Field Marshal Thanom Kittikachorn, who was overthrown and fled the country after the October 1973 uprising.
One of the reasons cited by the authorities to quell that rally was that the student activists had allegedly insulted the monarchy.
Jatuporn Prompan, chairman of the United Front for Democracy against Dictatorship, also warned in a Facebook broadcast on Tuesday that any demands that crossed the line would lead to a confrontation with the movement that seeks to protect the monarchy. This would end up in an incident similar to the 1976 tragedy, Mr Jaturporn warned.
He added that the protesters' three original demands were legitimate and likely to be succeed. "But crossing the line will render the student movement illegitimate and in the end, they will achieve nothing."
Senator Suwaphan Tanyuvardhana said some people had offended the "rights and feelings of tens of millions of Thai people loyal to the royal institution and the tradition of peaceful co-existence based on the mercy of the royal institution". His committee was worried about the development.