Iran's state TV, citing an unnamed official, says British-Iranian dual national Nazanin Zaghari-Ratcliffe is facing a new charge.
The report on Tuesday did not elaborate.
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Zaghari-Ratcliffe had been released from prison due to the coronavirus pandemic after serving nearly all of her five-year sentence. Zaghari-Ratcliffe was arrested during a holiday with her toddler daughter in April 2016. Her family says she was in Iran to visit family, denying that she was plotting against Iran.
Zaghari-Ratcliffe worked for the Thomson Reuters Foundation, the charitable arm of the news agency.