At least 100 people gathered in Bangkok on Sunday to call for more freedom as the country marked its second anniversary under military rule.
At Thammasat University, around 100 students and activists gathered to make speeches before marching on Democracy Monument in the heart of Bangkok.
Braving temperatures close to 40 degrees Celsius, the protesters called on the military government to allow freedom of expression and a return to democracy.
"They are solders with rifles in their hands and tanks at their backs and they are afraid of a few people wearing T-shirts with slogans," one protester shouted through a microphone.
The protesters, led by the New Democracy student group, also called on Thais to vote in an upcoming referendum against a constitution drafted by the junta which will see a military-appointed upper house of parliament.
"Vote No Against the Illegal Constitution," read one placard held by a protester.
Despite a ban on political gatherings, police monitoring the event made no move against the protesters, only asking them to remain on pavements to ease traffic congestion.
Near the monument, dozens of students belonging to the Young People for Social Democracy group also gathered to make a public statement.
"There is no reconciliation here, there is no accountability. We demand public participation," their leaders said.
Former prime minister Yingluck Shinawatra, whose government was overthrown by the military two years ago, took to Twitter and asked the junta to reflect on its rule.
"Today is the second anniversary of the coup d'etat that removed my government from office," she tweeted.
"More importantly it was the day that the people's rights and freedom were taken away.
"I wish that they will swiftly return happiness to the people.
"By happiness I mean the basic rights and freedom that will allow the people to once again choose their own destiny," she added, alluding to the junta's slogan after it took power when it promised to "return happiness to the people."
The rights monitoring centre, iLaw, also released a criticism of the junta on Sunday titled "24 months under military rule: When the soldier's powers are above the law."
The group has expressed its dissatisfaction over the past two years at the lack of checks and balance in tempering military power.
Thailand's military government took power in May 2014 after widespread political protest. The junta cited a broken political system and stagnating economy as reasons for the coup.