Dozens of Thai government supporters rallied in front of Parliament House in Bangkok on Monday in a counter-demonstration to recent student-led, anti-government protests.
Protests have been taking place almost daily since mid-July, challenging the government of Prime Minister Prayuth Chan-ocha and the conservative royalist establishment.
In a sign of more coordinated opposition to the students, a former nationalist activist, Sumet Trakulwoonnoo, 46, announced a new pro-government group, the Coordination Center of Vocational Students for the Protection of National Institutions (CVPI).
"A group of people is instigating young minors to come out and attack the military, the government and also involving the monarchy, and this could lead to violence and destruction of our system of governance and our culture," Sumet told reporters at the rally.
"We're setting up to remind youth groups, parents, teachers and officials about the danger to the nation from these people who are instigating youth to become godless and obsessed with Western culture, do drugs and hate their parents and teachers."
The protesters, led by student groups, have made a growing number of veiled references to the monarchy, a highly sensitive topic, and one speaker at a recent rally called for its reform.
Monday's pro-establishment demonstration took place less than 100 meters from a pro-democracy protest, but police kept watch and there was no trouble.
The rival demonstrations have revived concern about trouble in a country that was for roiled for more than a decade by sporadic street clashes between conservatives and their rivals loyal to former populist prime minister Thaksin Shinawatra.
The recent demonstrations have been much smaller.
Prime Minister Prayuth has said that the government is creating a way for political groups to express their views but he has voiced concern about confrontation.
The reaction from authorities to the pro-democracy protests has been limited but two activists were arrested on Friday on charges of sedition and breaking restrictions to stop the spread of coronavirus, prompting a protest by more than 1,000 people in Bangkok on Saturday.
The two were later freed on bail.
Human Rights Watch said that several protesters around the country had faced harassment by authorities, including six student leaders in Phitsanulok province in the north who were held without charge for nine hours.
"Legal action and harassment are intensifying despite Prime Minister Prayuth's promises that the government would listen to the dissenters' demands and concerns," said Sunai Phasuk, senior researcher on Thailand for Human Rights Watch.
The government denied ordering any harassment of critics.
"The government has not ordered the blocking of student activism," government deputy spokeswoman Rachada Dhnadirek told Reuters.
"We don't want to see violence or expressions beyond the bounds of the law," Rachada said.