In the two weeks since the military ousted Suu Kyi and put her under house arrest in the administrative capital Naypyidaw, big cities and isolated village communities alike have been in open revolt.

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

After her detention in a dawn raid on February 1 -- the day of the coup -- she was charged under an obscure import and export law, over walkie talkies that were found in her home during a search.

The Nobel laureate's lawyer told AFP Tuesday she had been hit with a second charge, of violating the country's disaster management law.

"She was charged under section 8 of the Export and Import law and section 25 of the Natural Disaster Management law as well," Khin Maung Zaw told AFP.

While it was unclear how the disaster law applied in Suu Kyi's case, it has been used against deposed president Win Myint -- also arrested on February 1 -- relating to a campaign event that the junta alleges broke coronavirus-related restrictions.

Khin Maung Zaw added that Suu Kyi and Win Myint, both of whom he has yet to have any contact with, were expected to appear via video conference during a March 1 trial.

The United States said it was "disturbed" by the news, and renewed demands for Suu Kyi's release.

"We call on the Burmese military to immediately release all unjustly detained civilian and political leaders, journalists and human rights activists and other members of civil society as well as to restore the democratically elected government," State Department spokesman Ned Price told reporters.

British Prime Minister Boris Johnson also voiced his condemnation, calling the charges against Suu Kyi "fabricated" and a "clear violation of her human rights".

"We stand with the people of Myanmar and will ensure those responsible for this coup are held to account," he tweeted.

More than 420 people have been arrested since the coup, according to a list of confirmed detentions from the Assistance Association for Political Prisoners monitoring group.

Military spokesman Zaw Min Tun said Tuesday that both Suu Kyi and Win Myint were in a "safer place" and "in good health".

"It's not like they were arrested -- they are staying at their houses," the general, who became the country's vice-minister of information after the coup, told a press conference.

- 'They want to do bad things' -

Security forces have used increasingly heavy measures to quell huge nationwide street protests and a disobedience campaign encouraging civil servants to strike.

Troops have fanned out around the country in recent days.

Rubber bullets, tear gas and even sling shots have been used against protesters, and one demonstration in Mandalay on Monday saw police beating journalists hours before authorities again cut internet access.

"They shut down the internet because they want to do bad things," Win Tun, a 44-year-old who lives in the commercial capital Yangon, said Tuesday.

"We didn't sleep the whole night so we could see what would happen."

Undeterred, crowds returned to the streets of Yangon and around the country on Tuesday.

"I want more people to join the protests, we don't want to be seen as weak," said university student Thwe Ei Sann.

A large crowd blocked railway tracks outside Mawlamyine to prevent a Yangon-bound train from leaving the port city.

Many of the country's train drivers have joined the anti-coup work boycotts, frustrating junta efforts to restart the national railway network after a Covid-19 shutdown.

Early Wednesday, Britain-based monitoring group NetBlocks confirmed that Myanmar was once again experiencing a "near-total internet shutdown".

- 'Not what China wants to see' -

The United States and Britain were not alone in their condemnation of the leaders of Myanmar's new military administration, which insists it took power lawfully.

The Chinese ambassador to Myanmar said Tuesday that "the current development in Myanmar is absolutely not what China wants to see".

He added that Beijing had good relations with Suu Kyi's National League for Democracy party.

So far, only Washington has announced targeted sanctions against the generals, calling on them to relinquish power.

Military spokesman Zaw Min Tun said that "sanctions are expected", and that the regime would continue to "maintain friendly relations" with the international community.

UN envoy Christine Schraner Burgener spoke to junta number two Soe Win on Monday and warned him that the regime's network blackouts "undermine core democratic principles", according to a spokesman.