A seven-year-old girl has died in her home when security forces opened fire in Myanmar’s second city Mandalay – the youngest victim so far in a crackdown against opposition to last month’s military coup.

The ruling junta accused pro-democracy protesters of arson and violence during the weeks of unrest and said it would use the least force possible to quell the daily demonstrations.

Junta spokesman Zaw Min Tun said 164 protesters had been killed in total and he expressed sadness at the deaths.

The Assistance Association for Political Prisoners (AAPP) activist group says at least 261 people have been killed in the security forces’ crackdown.

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“They are also our citizens,” Zaw Min Tun told a news conference in the capital Naypyitaw, a day after the European Union and the United States imposed more sanctions on groups or individuals linked to the February 1 coup that ousted Aung San Suu Kyi’s elected government.

Staff at a Mandalay funeral service told Reuters that a seven-year-old girl had died of bullet wounds in Chan Mya Thazi township on Tuesday.

Soldiers shot at her father but hit the girl who was sitting on his lap inside their home, her sister told Myanmar Now media outlet.

Hundreds of protesters have been killed. Photo: AAP

Two men were also killed in the township, it said.

The military had no immediate comment on the incident.

As night fell, candle-lit vigils were held in the commercial capital Yangon and other cities.

The junta has faced international condemnation for staging the coup that halted Myanmar’s slow transition to democracy and for its lethal suppression of the protests that followed.

It has tried to justify the takeover by saying a November 8 election won by Suu Kyi’s National League for Democracy (NLD) was fraudulent – an accusation the electoral commission has rejected.

Military leaders have promised a new election but have not set a date and have declared a state of emergency.

The junta’s Zaw Min Tun blamed the bloodshed on the protesters and said nine members of the security forces had been also killed.

“Can we call these peaceful protesters?” he said, while showing a video of factories on fire.

“Which country or organisation would regard this violence as peaceful?”

Myanmar’s military Junta charged deposed de-facto leader Aung San Suu Kyi with accepting bribes and taking illegal payments in gold. Photo: AAP

He said strikes and hospitals not fully operating had caused deaths, including from COVID-19, calling them “undutiful and unethical”.

The spokesman also accused media of “fake news” and fanning unrest and said reporters could be prosecuted if they were in contact with the CRPH, as the remnants of Ms Suu Kyi’s government is known.

The military has declared the CRPH an illegal organisation and said membership is punishable by death.

In the more than three-hour news conference, he gave granular details on how the NLD had created hundreds or even thousands of extra ballots in numerous townships by inventing voters, including in Ms Suu Kyi’s own constituency.

Videos showed people saying they were paid by NLD representatives.

The NLD has denied making any attempt to rig the election.

Also shown was video testimony of former Yangon chief minister Phyo Min Thein saying he visited Ms Suu Kyi multiple times and gave her money “whenever needed”.

Ms Suu Kyi, who won the Nobel Peace Prize in 1991 for her campaign to bring democratic civilian rule to Myanmar, has been in detention since the coup and faces charges that her lawyer says have been cooked up to discredit her.

-AAP