Around 80 people are appearing in court in Myanmar in connection with a student protest that ended in violence.
The group took part in a protest two weeks ago to demand changes to a controversial new education bill.
They were arrested in the town of Letpadan as they tried to force their way through police lines.
Video footage showing people being cornered by police and beaten with sticks sparked international condemnation.
But President Thein Sein has defended the action of officers, telling the BBC that in many Western countries a similar situation might have ended in gunfire and death.
The BBC’s Jonah Fisher says the students face charges of sowing disunity and encouraging instability, which carry jail terms of up to six years.
Our correspondent, who is at the court, says relatives and supporters have gathered outside the building with flowers, water and food.
One man waiting outside the jail on Wednesday told AFP news agency his daughter, Phyo Phyo Aung, had still not been told what charges she faced.
The students began a protest march from Mandalay to Yangon (also known as Rangoon) in January, in opposition to a bill which centralises control over higher education.
They were calling for more power to be devolved to universities and higher education institutions, the right to form student unions, and teaching in ethnic minority languages.
The two sides had been in negotiations, and the authorities had agreed to let the students continue to Yangon.
But the students were angered by police opposition when they reached Letpadan, 140km (90 miles) north of Yangon, and clashes broke out as they attempted to break through police lines.
Scores of students and some police officers were injured, while more than 100 people were arrested.
The scenes were a reminder of Myanmar’s authoritarian military past, from which it began to emerge four years ago under a nominally civilian government.
Our correspondent says the march was technically illegal as it did not have official approval. The government has announced an enquiry into the response of the security services, state media report.
Young Burmese have been at the forefront of several protests in Myanmar over the years, including a notorious 1988 uprising against the former ruling junta.