A Myanmar military court has sentenced ousted leader Aung San Suu Kyi and her economic adviser, an Australian academic, to three years in prison.

A closed court in the capital Naypyidaw convicted the Nobel Peace Prize laureate alongside Sean Turnell, honorary professor of economics at Macquarie University in Sydney, of breaching the country’s Official Secrets Act, punishable by a maximum sentence of 14 years in prison.

The couple pleaded not guilty last month.

The Australian Department of Foreign Affairs and Trade confirmed Turnell’s conviction to the Financial Times. Turnell also faces charges of violating the country’s immigration law.

Aung San Suu Kyi, 77, has previously been sentenced to 20 years in prison on multiple charges, including corruption and incitement to the junta. She received a three-year sentence with hard labor earlier this month for electoral fraud.

Turnell, who previously worked at the Reserve Bank of Australia, was arrested following a February 2021 coup in which the military overthrew the democratically elected government of Aung San Suu Kyi.

The trials were held behind closed doors and a gag order prevented lawyers for the defendants, who had limited access to their clients, from speaking to the media.

Earlier this month, a military court sentenced former British ambassador Vicky Bowman and her husband, dissident artist Htein Lin, to one year in prison for immigration offences.

In the past, convictions of foreign nationals in Myanmar have preceded their release and deportation, with sentences commuted or charges dropped.

Amnesty International called the decision “pure sham” and “the latest in a series of politically motivated cases, all designed to cement the power of the rights-abusing Myanmar military”.

Burma’s army, known as the Tatmadaw, has arrested more than 15,000 people and killed more than 2,000 since February’s coup, according to local advocacy group Assistance Association for Political Prisoners.