At least 38 people have been killed in the latest crackdown by security forces against anti-coup protesters in Myanmar, according to an advocacy group, as the military government declared martial law over two townships in the country’s largest city, Yangon.

The death toll reported on Sunday by the Assistance Association for Political Prisoners (AAPP) group matched that of March 3, which had previously recorded more fatalities than any other day since mass demonstrations against the February 1 military takeover began six weeks ago.

AAPP said in a statement a total of 126 people have so far been killed in “violent and arbitrary crackdowns” since the coup, warning that “casualties are drastically increasing”. More than 2,150 people have also been arrested by Saturday, it added.

On Sunday, plumes of smoke rose over the massive Hlaing Thar Yar township in Yangon, where security forces opened fire on protesters. At least 22 civilians were killed and more than 20 wounded, including three in critical condition, according to AAPP.

Throughout the day, gunshots were heard continuously by residents hiding in their homes, while military trucks were sighted driving through Hlaingthaya’s streets.

A doctor told the AFP news agency that she had treated about 50 people with injuries. “I cannot talk much – injured people keep coming,” she said before hanging up.

AAPP reported a “similarly extreme crackdown” in other parts of the country, including the second city of Mandalay, where a woman was shot dead, and in Bago, where two people were killed.

Meanwhile, state television MRTV said a police officer had died of a chest wound after a confrontation with protesters in Bago. He is the second policeman reported dead in the protests.

Also on Sunday, state media said martial law had been declared over Hlaing Thar Yar and the neighbouring Shwepyitha township.

The military government “gives administrative and judicial martial law power to the Yangon regional commander to practice [in Hlaingthaya and Shwepyitha townships] … to perform security, maintain the rule of law and tranquillity more effectively,” said an announcer on state television.

Doctor Sasa, a representative of elected lawmakers from the assembly that was removed by the army, voiced solidarity with the people affected by the military government’s move.

“The perpetrators, attackers, enemies of the people of Myanmar, the evil SAC (State Administrative Council) will be held accountable for every drops of blood that shed,” he said in a message.

The United Nations’ envoy for Myanmar strongly condemned the continuing bloodshed in the country.

“The international community, including regional actors, must come together in solidarity with the people of Myanmar and their democratic aspirations,” Christine Schraner Burgener said in a statement on Sunday.

She said the Myanmar military was defying international calls for restraint, adding she had heard “heartbreaking accounts of killings, mistreatment of demonstrators and torture of prisoners” from contacts inside the Southeast Asian country.

“The ongoing brutality, including against medical personnel and destruction of public infrastructure, severely undermines any prospects for peace and stability,” she said.

In a statement, Dan Chugg, the United Kingdom’s ambassador to Myanmar, also said the British government “is appalled by the security forces’ use of deadly force against innocent people” in Yangon and other parts of Myanmar.

China says factories burned

Meanwhile, China’s embassy in Myanmar said many Chinese staff were injured and trapped when factories in Hlaing Thar Yar were looted and destroyed by unidentified attackers.

The embassy asked for security to be guaranteed quickly, a statement on the embassy’s Facebook page said, describing the situation as “very severe”. It said Chinese citizens in Myanmar had also been warned.

“Some Chinese businesses’ factories were looted and destroyed and many Chinese staff were injured and trapped,” it said, without giving details of injuries.

Opponents of the coup have criticised China for not coming out more strongly against the army takeover as Western countries have done. China has said that the priority is stability and that it is Myanmar’s internal affair.

In its statement, AAPP said “junta forces did not leave the streets and wards and they violated and arsoned neighbourhoods [in Hlaing Thar Yar].”

The latest crackdown came a day after Mahn Win Khaing Than, who is on the run along with most senior officials from the Aung San Suu Kyi’s National League for Democracy (NLD) party, said the civilian government would seek to give people the legal right to defend themselves.

Aung San Suu Kyi is due to return to court on Monday. She faces at least four charges, including the illegal use of walkie-talkie radios and infringing coronavirus protocols.

The army said it took power after its accusations of fraud in a November 8 election won by the NLF were rejected by the electoral commission. It has promised to hold a new election, but has not set a date.