Reporters Without Borders says the American journalist on a hunger strike for two weeks to protest her imprisonment in Iran was briefly hospitalized after she intensified her fast by refusing to drink water.

The press freedom group said Monday that 32-year-old Roxana Sabeiri was taken Friday to a clinic at Tehran's Evin prison, where she is being held. She was released within a day after again drinking water.

Sabeiri's Iranian-born father said last week his daughter was drinking only sweetened water, while refusing food to protest her eight-year jail sentence for allegedly spying for the U.S. Reporters Without Borders says her father told the group she stopped drinking water after Iran denied that she was on a hunger strike.