Australia's Department of Foreign Affairs said it is providing consular assistance to two of its nationals in Myanmar who have been detained by officials.
"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 Friday.
The couple run a bespoke consultancy business in Yangon.
A third Australian, economist Sean Turnell, an advisor to Suu Kyi, who was arrested a week after the coup also remains in custody.
It comes as the death toll rose, with one man killed on Sunday in the central city of Monywa.
At least two others were injured during 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.
Anti-coup protests continued in Mandalay despite the intensifying violent crackdowns on demonstrators by security forces. Source: AAP
"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."
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.
Mourners in the city laid to rest a 26-year-old who died 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.
A hearse carrying the body of Saw Pyae Naing is driven in Mandalay, Myanmar. Source: AAP
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.
