Sunday's death toll reported by the Assistance Association for Political Prisoners equaled the number killed March 3, which was then the bloodiest day since the Feb. 1 military coup.

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The group said over 120 people have been killed as security forces seek to quell protests against military rule that continue daily across the country.

Over 20 people were killed in the Hlaingthaya township of Yangon as security forces fired on protesters, according to local media.

Martial law was declared in Hlaingthaya and neighboring Shwepyithar township on Sunday in the first such act since the coup, followed by declarations in four more townships in the city on Monday.

It marked a departure for the military that had until now used the State Administration Council, the top decision-making body set up following the coup, to rule.

The declaration allows the military, more precisely the commander of the Yangon Region Command, to exercise all administrative and judicial authority in the townships, possibly indicating harsher crackdowns on protesters in the days to come.

Security forces block the road as people continue to protest against the military coup in Yangon, Myanmar on March 14, 2021. (Anadolu Agency/Getty/Kyodo) 

In an industrial park in Hlaingthaya, Chinese-linked factories were attacked Sunday, including by arson, leaving many people injured, according to the Chinese Embassy in Myanmar.

The factories may have been targeted because China has taken a position friendly toward Myanmar's military government in the U.N. Security Council over the toppling of the country's elected government.

The military said on state TV on Sunday night that a police officer died and three other people were injured in Bago, a region northeast of Yangon.

British Ambassador to Myanmar Dan Chugg said in a statement that the British government is "appalled" by the security forces using deadly force against innocent people.

"We call for an immediate cessation of this violence and for the military regime to hand back power to those democratically elected by the people of Myanmar," he said.

Besides the restoration of civilian rule, the protesters are calling for the release of elected leaders, including Aung San Suu Kyi, who were ousted in the coup.

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