An Iranian opposition leader held under house arrest since 2011 has ended his hunger strike after the authorities accepted one of his two demands.
Mehdi Karroubi, 79, stopped eating and drinking on Wednesday to press for a public trial and the removal from his home of intelligence ministry agents.
On Thursday morning, he was admitted to hospital with high blood pressure.
Later, his son announced that he had ended the strike after "the withdrawal of the agents from his house".
Mehdi Karroubi and fellow reformist Mir Hossein Mousavi, 75, were candidates in Iran's disputed presidential election in 2009, which was won by the hardline incumbent Mahmoud Ahmadinejad.
Millions of opposition supporters took to the streets to demand a re-run of the vote amid allegations of widespread fraud.
But Supreme Leader Ayatollah Ali Khamenei insisted the result was valid and ordered a crackdown on dissent that saw dozens of opposition supporters killed and thousands detained.
Mr Karroubi and Mr Mousavi, along with his wife Zahra Rahnavard, were placed under house arrest six years ago after the Arab Spring sparked fresh protests. They have never been formally charged.
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Mr Karroubi's wife, Fatemeh, told the Saham News website on Wednesday that her husband would end his hunger strike only if the authorities met his demands for the agents to be removed from their home and for a trial date to be set.
"He does not expect a fair trial, but wants it to be public and would respect the verdict," she said.
But early on Thursday, his son Mohammad Taghi tweeted: "At 01:00, father was sent to hospital due to the hunger strike. Pray a lot."
He later told BBC Persian that his father was in intensive care and was still not accepting food or water. In response, doctors put him on an intravenous drip.
The cleric had a pacemaker fitted earlier this month and was prescribed heart medication, which he continued to take after starting the hunger strike.
On Thursday afternoon, Mohammad Karroubi told BBC Persian that his father had ended the strike after meeting high-ranking security officers, who he said had agreed to withdraw the agents from his home.
The demand for a public trial had not yet been met, he added.
Mohammad Karroubi was separately quoted by Saham as saying that his father would have to stay in the coronary care unit at the hospital for another 48 hours.
Many reformist figures, including former President Mohammad Khatami, had urged the current president, Hassan Rouhani, to meet Mr Karroubi's demands.
In March, a court sentenced Mr Karroubi's eldest son, Hossein, to six months in prison after convicting him of circulating "propaganda against the regime". He published a letter his father wrote to Mr Rouhani calling for a trial.