The son of one of the world's most recognised pro-democracy activists fears she could die in a "hellhole" prison amid reports she has a serious health condition.
Little has been seen of Myanmar's former leader Aung San Suu Kyi since her government was overthrown by the military junta in 2021.
The Nobel Laureate has been imprisoned by the military since the coup and her location is currently unknown.
One of Suu Kyi's last public appearances was in May 2021, when she was filmed attending a court hearing. Footage on state television showed her sitting upright in the dock, with her hands on her lap.
Reports recently emerged that she was locked in solitary confinement and suffering from a serious heart condition.
The activist's London-based son, Kim Aris, called on the military to immediately release his mother.
"I've heard that her heart condition is getting worse. It's reported that she was saying that the pain was getting worse and that her blood pressure had dropped," he told the ABC.
"She's 80 years old. She's locked up in some hellhole in Burma. I'm worried she might die any day if she's not dead already."
Jailed with no contact
Suu Kyi was widely seen as a beacon for human rights after serving as the general secretary of Myanmar's opposition to the ruling military junta since the late 80s.
In 1991, she was awarded the Nobel Peace Prize for her "non-violent struggle for democracy and human rights".
But after leading Myanmar for five years from 2015, her party was overthrown and she was imprisoned by the military junta, which has maintained control over the country since.
Suu Kyi is serving a 27-year sentence for offences including incitement, corruption and election fraud — charges she denies.
The only contact Mr Aris has had from his mother since she was jailed was a single letter he received more than two years ago.
"Other than that, I've had no communication from her," he said.
"I've sent care packages and letters, but I received no response because the military don't allow any response to come back to me."
The military government of Myanmar did not respond to the ABC's questions, but previously said reports of Suu Kyi's ill-health were false.
Fears upcoming Myanmar elections will be 'orchestrated'
Concerns for Suu Kyi's health come amidst a violent civil war in Myanmar that has been raging since her government was overthrown.
More than 52,700 people have been killed in conflict in Myanmar since the 2021 coup, including almost 10,000 civilians, according to the Armed Conflict Location and Event Data (ACLED), a US-based conflict monitor.
The military has announced elections starting in December, but with Suu Kyi and more than 22,000 political prisoners in jail, experts have called it a sham.
"It has all the hallmarks of being a manipulated and orchestrated event … to give the appearance of a democratic transition," Nicholas Coppel, who was Australia's ambassador to Myanmar between 2015 and 2018, told the ABC.
"But at the end of the day, the same people will be in charge. You can rest assured about that."
While Suu Kyi still has a "phenomenal following" within Myanmar, Mr Coppel said it would likely take more than peaceful protest to achieve democracy again.
"I think the people of Myanmar have decided that it's going to require the military to be overthrown, and they can't be relied upon for a peaceful transition to a genuinely democratic country," he said.
