Paris, Dec 27 (AP) A French-Iranian researcher locked up in Tehran's notorious Evin Prison has gone on a hunger strike along with an academic and co-prisoner from Australia, a rights group said.

The hunger strikes by Iranian-born French researcher Fariba Adelkhah and Kylie Moore-Gilbert were revealed by the Center for Human Rights in Iran. They were confirmed by Sciences Po's research centre CERI, where Adelkhah works.

French researchers expressed their concern in tweets and press commentaries.

An open letter was sent to the US-based Center for Human Rights in Iran signed with the names of the two women after it was received "by a source with contacts inside the prison", the centre said in a Christmas Eve statement.

The centre quoted the letter as saying that the women were starting "their joint hunger strike in the name of academic freedom" on behalf of researchers like themselves "unjustly imprisoned on trumped up charges".

The letter said they had been subjected to psychological torture and human rights violations. It said they are being held in Ward 2-A, allegedly run by the Islamic Revolutionary Guard Corps.

Iranian officials disclosed in July the arrest of Adelkhah, a prominent anthropologist who often travelled to Iran for her research on post-revolutionary Iranian society.

They said she was arrested on espionage charges. Her friend and fellow researcher Roland Marchal was arrested as he tried to visit her, France revealed in October. He is being held in a men's ward.

Moore-Gilbert, a University of Melbourne scholar on the Middle East, has been jailed since October 2018.

On Thursday, the Center for Human Rights in Iran published a letter she addressed in June to Australia's prime minister, pleading for help, and an update this month in which she begs him "to take immediate action". Two Australians were freed from Iran in October while Australia freed an Iranian in what appeared to be a prisoner swap.

Australian Foreign Minister Marise Payne said at the time that Moore-Gilbert's situation was "more complex".

Meanwhile, Iran indicated a willingness to make prisoner exchanges with the United States after freeing a Chinese-American scholar from Princeton held for three years in a prisoner swap.

A fellow scholar and friend of Adelkhah, Jean-Francois Bayart, and researcher Beatrice Hibou wrote in Thursday's Le Monde newspaper that the women's determination should not be doubted. They noted that Adelkhah had earlier created a discussion group for women on Telegram, an encrypted social network, calling it the Lionesses.

"Having known her for a long time, we know she is ready to die like a lion to defend her freedom, that of her job and her dignity," they wrote. (AP)

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