French researcher chronicles 9 months of misery in Iran jail

In his first public statements since returning to France as part of a prisoner exchange, Marchal said the isolation was worse than the interrogations.

"I was not physically tortured, but I suffered greatly from my confinement, and above all, my isolation," he said in a written message transmitted by his support group of friends and colleagues.

"Much more than the interrogations, it is confinement - very different to the type imposed on us because of the coronavirus - which proved very painful," he said.

"Only the books... to which I had partial access, and friendships struck with a few inmates allowed me to hold on in a universe where each day resembles the previous and the next," Marchal said.

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Imprisoned in Iran since June 2019, Marchal was freed by Iran on March 20 after France released an Iranian, Jalal Rohollahnejad, who was facing extradition to the United States on accusations he tried to smuggle technology materials into Iran in violation of American sanctions.

Marchal and his partner, fellow researcher Fariba Adelkhah, were detained on accusations of plotting against national security. The pair, who work at the Centre for International Studies at the prestigious Sciences Po university in Paris, have denied the charges.

Adelkhah remains in jail. She has both French and Iranian citizenship, but Tehran does not recognise dual nationality.

Marchal said he had been able to see Adelkhah "only three times" during his imprisonment, each time for a few minutes and "under strict surveillance of interrogators".

He became aware only afterwards that she went on a hunger strike that lasted 49 days to protest Iran's detention of researchers. Adelkhah stopped her protest in February at the urging of her support committee after her health deteriorated sharply.

Marchal thanked everyone who contributed to his liberation, and who are "continuing to mobilise for Fariba's" freedom.

Iran, the Middle Eastern country most affected by the coronavirus pandemic, has reported more than 58,000 infections, a figure that some foreign experts suspect is an underestimate.

The country's prison inmates have been hit particularly hard.

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