An Iranian opposition leader held under house arrest since 2011 has been admitted to hospital a day after he began a hunger strike, his family says.
Mehdi Karroubi stopped eating and drinking to press the authorities to give him a public trial and remove security agents from his house.
The 70-year-old cleric was taken to a hospital in Tehran in the early hours of Thursday due to high blood pressure.
He suffers from heart disease and has required hospital treatment before.
Mr 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 were placed under house arrest six years ago after the Arab Spring sparked fresh protests. They have never been formally charged.
‘Pray a lot’
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 two demands.
The first was the removal of intelligence ministry agents inside their home as well as recently-installed security cameras, which she said had “no precedent before or after the [1979 Islamic] Revolution in any house arrest”.
The second demand was for a date for a public trial to be set in accordance with the constitution. Mrs Karroubi said her husband would respect the verdict even though he “does not expect a fair trial”.
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, the doctors had put him on an intravenous drip, he added.
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His father had a pacemaker fitted earlier this month and is prescribed heart medication, which he continued to take after starting the hunger strike.
Mohammad Karroubi also said former President Mohammad Khatami had told the Karroubi family that the intelligence ministry should be able to withdraw its 12 agents from their home.
Supporters of Mr Karroubi and Mr Mousavi repeatedly urged current President Hassan Rouhani to release the two men during his re-election campaign this year.
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.