More than 80 people have been killed since in mass protests since the military wrenched civilian leader Aung San Suu Kyi from power - a toll expected to rise dramatically after Sunday's violence.

The junta has repeatedly justified its power grab by alleging widespread electoral fraud in November's elections, which Suu Kyi's National League for Democracy party won by a landslide.

State-run media announced late Sunday that Yangon's massive Hlaing Tharyar township and the neighbouring Shwepyitha township will be placed under martial law.

The vast and impoverished townships are known as factory hubs and home to garment factories.

The junta "gives administrative and judicial martial law power to the Yangon regional commander... to perform security, maintain the rule of law and tranquility more effectively," said an announcer on state-run TV.

Soldiers and police have in recent weeks been staging near-daily crackdowns against demonstrators calling for a return to democracy -- deploying tear gas and firing rubber bullets and live rounds to quell anti-coup protests.

In Hlaing Tharyar township police and soldiers clashed violently with protesters wielding sticks and knives who hid behind makeshift barricades.

Protesters using cut-out trash cans as shields managed to retrieve protesters who were wounded when the security forces opened fire, but a doctor said not all could be reached.

"I can confirm 15 have died," the doctor told AFP, adding that she had treated about 50 people and expects the death toll to climb.

"I cannot talk much -- injured people keep coming," she said before hanging up.

The Assistance Association for Political Prisoners monitoring group -- which verifies arrests and fatalities since the coup -- confirmed a higher death toll.

Residents hiding at home heard gunshots continuously throughout the day, while military trucks were seen driving through the smoky streets.

Former colonial power Britain issued a statement through its embassy in Yangon saying it was "appalled" by the use of force "against innocent people" following the Sunday violence.

The statement, signed by ambassador Dan Chuggi, called for an "immediate cessation of this violence" and for the regime to return power to the elected civilian officials.

- 'I will fight until the end' -

Hours before violence erupted in the township a police officer posted a TikTok video saying in a voiceover that security forces would be bringing heavy weaponry.

"I will not have mercy on Hlaing Tharyar and they will fight back seriously too because there are all kinds of characters there," said the officer under the account @aungthuraphyo40.

"We should not have mercy on them."

The video, which was seen and verified by AFP factcheckers, was removed hours later.

State-run media said that five factories in the garment-producing township had been razed.

Among the burned buildings were Chinese-owned factories, Beijing's embassy in Myanmar said, condemning actions of the "destroyers" in a statement posted on their official Facebook account.

The embassy "quickly urged local police to guarantee the security of Chinese businesses and personnel," it said.

The evening news confirmed a death in Tamwe township, saying that security forces opened fire when hundreds of protesters attempted to torch a police station.

Scenes of chaos unfolded elsewhere in Myanmar -- one man was shot dead in northern Hpakant city and another woman was killed from a headshot in Mandalay.

Despite the bloodshed, those in the anti-coup movement remain defiant.

"I've seen the fallen heroes give their lives," said 21-year-old Ma Khine Lay, admitting she was afraid even as she rebuilt barricades out of bricks and bamboo poles in a Yangon township.

"I will fight until the end."

- 'The darkest moment of the nation' -

A group of elected MPs, many of whom are in hiding, have formed a shadow "parliament" called the Committee for Representing Pyidaungsu Hluttaw (CRPH) -- the Burmese word for the country's governing bloc.

They issued a statement saying protesters had the "full right to defend themselves" under the country's penal code against security forces.

Their acting vice president on Saturday called for the people to continue protesting against the "unjust dictatorship".

"This is the darkest moment of the nation and the light before the dawn is close," said Mahn Win Khaing Than in a recorded video posted on the CRPH's Facebook page.

A high-ranking NLD politician who served as speaker of the house during Suu Kyi's previous administration, he was placed under house arrest during the February 1 power grab, according to a local monitoring group.

His Saturday address echoed the anti-coup movement's calls for a "federal democracy" -- which would allow ethnic minority groups to have a role in Myanmar's governance.

"The uprising must win," he said.

The junta has said the CRPH's formation is akin to "high treason" which carries a maximum sentence of 22 years in jail.

bur-dhc/ch

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