Government spokesman Major General Zaw Min Tun told the Voice of Myanmar and Yangon Media Group on Thursday that Professor Turnell, Japanese filmmaker Toru Kubota and ex-British diplomat Vicky Bowman, as well as an unidentified American, had been released and deported.
Myanmar's state-run MRTV later confirmed the reports.
Prof Turnell, 58, who holds an honorary position in the Department of Economics at Sydney's Macquarie University, was working in Myanmar as an adviser to ousted leader Aung San Suu Kyi when arrested in 2021 after the military seized power in a coup.
In September he was sentenced to three years in prison for violating the country's official secrets law and immigration law.
His friend, economist Tim Harcourt, said Prof Turnell dedicated himself to helping improve the lives of people in Myanmar, but got caught up in the coup.
"His heart was in the right place. He was trying to improve the lives of ordinary people in Myanmar," he told Sky News.
"Thank goodness he's been released now.
"The priority for Sean is to get back and be with his wife. Let's hope he can get home and recover."
Foreign Minister Penny Wong said Australia welcomed the reports.
"Professor Turnell continues to be our first priority ... as such, we will not be commenting further at this stage," she wrote on Twitter.
Independent federal MP and former ABC foreign correspondent Zoe Daniel said she had received corroborated information about the release.
"Holding breath with relief and hope for his health and well-being," she tweeted.
Ms Daniel has been a consistent advocate for Prof Turnell's release.
Prime Minister Anthony Albanese most recently raised the case with his Vietnamese counterpart Pham Minh Chinh on the sidelines of the ASEAN summit on Saturday.
"I do want to thank Vietnam for your advocacy for Professor Sean Turnell, who has been detained in Myanmar," he said at the time.
Mr Kubota, a 26-year-old Tokyo-based documentary filmmaker, was arrested on July 30 after taking images and videos of a small flash protest against the military takeover last year.Â
He was convicted last month by the prison court of incitement for taking part in the protest and other charges, and was sentenced to 10 years in prison.
Ms Bowman, 56, a former British ambassador to Myanmar, was arrested with her husband, a Myanmar national, in Yangon in August. She was given a one-year prison term in September for failing to register her residence.
AAP with AP and Reuters
16°C