Security forces in Myanmar shot dead an anti-coup protester on Sunday, as the Australian government confirmed it is assisting two nationals who were detained after trying to leave Yangon.

Myanmar has been in turmoil since soldiers ousted civilian leader Aung San Suu Kyi last month, triggering nationwide protests demanding a return to democracy.

Security forces have responded with lethal force, using live rounds along with tear gas and rubber bullets in an effort to bring the demonstrations to heel.

One man was killed on Sunday in the central city of Monywa and at least two people were injured in a clash with security forces at barricades, two witnesses told AFP.

"I saw people carrying a man who was shot and killed,” a local resident told AFP, adding the body was taken to a local hospital.

"They used stun grenades and tear gas... later they started shooting. I don’t know if the man, who died on the spot after he was hit on his head, was killed from rubber bullets or live rounds.”

Australians in custody 

Australia’s foreign ministry confirmed on Sunday it was providing consular assistance to two of its nationals in Myanmar.

"Due to our privacy obligations we will not provide further detail,” a spokeswoman said.

It is understood business consultants Matthew O’Kane and Christa Avery, a dual Canadian-Australian citizen, are under house arrest after trying to leave the country on a relief flight on Friday.

The couple run a bespoke consultancy business in Yangon.

A third Australian, economist Sean Turnell, an adviser to Suu Kyi, who was arrested a week after the putsch also remains in custody.

Weekend violence failed to deter hundreds of doctors and nurses donning hard hats and brandishing posters of Suu Kyi as they marched at dawn through Mandalay, Myanmar’s second-largest city and cultural capital.

Later other demonstrators placed protest signs in pot plants along a street.

By afternoon there were barricades set on fire, gunfire in the streets and at least four people injured, a doctor in Mandalay said.

Mandalay has been the scene of some of the worst violence from police and soldiers since the coup.

The protests came a day after a local monitoring group confirmed the killing of four protesters at the hands of security forces around the country.

Two of the deaths were in Yangon, the country’s commercial hub, according to the Assistance Association for Political Prisoners (AAPP).

Mother mourns ‘hero son’ 

Mourners in the city laid to rest a 26-year-old who died on Saturday while in custody after being shot and arrested the previous night.

Myo Myint Aung’s mother cried over the coffin at the funeral service, saying that her son was still a child in her eyes.

"I am really proud of what you did for democracy and this country,” she said, in a video of the funeral service posted on social media.

"You are a real hero.”

A funeral was also held for mother-of-three Mar La Win, 38, who died earlier this weekend in the central city of Pakokku along the Irrawaddy river.

"My family is broken now,” her husband Myint Swe told AFP as the red flag of Suu Kyi’s political party was draped on her coffin surrounded by flowers.

Elsewhere the heartbroken family of 15-year-old Aung Kaung Htet, who was shot in the forehead at a protest at Tamwe, Yangon, paid tribute to the teenager.

Mourners held up the three-finger salute — a symbol of defiance — at his funeral.

Overnight, protesters staged a candlelit protest in the northern town of Kale and left signs on the street calling for United Nations intervention to stop the violence in Myanmar.

Nearly 250 deaths have been confirmed in the weeks since the coup, the AAPP reported, although the true toll could be higher.

More than 2,300 others have been arrested, the group said.

International condemnation by Washington, Brussels and the United Nations has so far failed to halt the bloodshed.

European Union foreign ministers are expected to approve sanctions against 11 junta officials at a meeting on Monday.