Ousted Myanmar leader Aung San Suu Kyi has made a surprise appearance in court - a day before she was scheduled to do so and without her lawyer present, reports said Wednesday.

Suu Kyi's lawyer Khin Maung Zaw said Suu Kyi appeared before the court via video link and without representation. The hearing had earlier been scheduled for Wednesday. He said the court had yet to recognize him as her lawyer and he had been barred from seeing her since she was detained by the military.

She was charged with violating the country's disaster management law. There were no other details. The disaster management law has been used against deposed president Win Myint for an election campaign event that the junta claims broke coronavirus restrictions. After her detention Feb. 1, Suu Kyi was charged for possessing unregistered walkie-talkies found in her home.

Her lawyer said Suu Kyi and Win Myint were now expected to appear via video link during a March 1 trial.

Myanmar's anti-coup protesters returned to the streets in force Wednesday with the biggest demonstrations since troops fanned out around the country to quell opposition to the new military junta.

Much of the country has been in open revolt since the military deposed Nobel laureate Aung San Suu Kyi's government at the start of the month and charged her under an obscure import law.

Tens of thousands rallied in Yangon, with protesters blocking roads with vehicles to stop security forces from moving around the nation's biggest city.

"We have to fight until the end," Nilar, a 21-year-old student who asked not to use her real name, told Agence France-Presse.

"We need to show our unity and strength to end military rule. People need to come out on the streets."

Wednesday's crowds came in defiance of more violent efforts by the regime to bring resistance to heel, following nationwide street protests and a disobedience campaign encouraging civil servants to strike.

Demonstrations over the past two days had been noticeably smaller since troops were deployed around Yangon on the weekend.

But social media was flooded with calls for a show of force by protesters in the hours before the junta imposed a third consecutive overnight internet blackout.

By noon, there were anti-coup demonstrations across Myanmar, from the remote highlands region of Chin state to a small town in the Irrawaddy delta that saw a parade of protesters hoisting Suu Kyi posters.

Right outside the capital Naypyidaw, tens of thousands of people from different sectors - including engineers, doctors and teachers - marched through the logging town of Pyinmana carrying signs saying "Help Myanmar."

U.N. special rapporteur Tom Andrews warned that reports of soldiers being brought into Yangon could lead to the situation there spiraling out of control.

"We could be on the precipice of the military committing even greater crimes against the people of Myanmar," he said.

There were no signs of a major troop mobilization in Yangon Wednesday morning.

In recent days, rubber bullets, tear gas and even slingshots have been used against protesters.

One young woman remains in a critical condition in Naypyidaw after being shot in the head last week.

The military said a police officer had died in Mandalay after a confrontation with protesters Sunday.

"Those who committed lawless action on the police officer will be dealt with as necessary," an army statement said.

The military justified its power seizure by alleging widespread voter fraud in November elections won by Suu Kyi's party in a landslide.