26 July 2013 Last updated at 14:42

Fears over health of Mehdi Karroubi, Iran opposition leader

Fresh concerns have been raised about the health of Iranian opposition leader Mehdi Karroubi, under house arrest since 2010.

Mr Karroubi's son said he was taken to hospital three times recently due to heart and lung problems.

Mehdi Karroubi, 76, was detained after anti-government street protests. He has not been formally charged.

Mr Karroubi lost to Mahmoud Ahmadinejad in presidential elections in 2009, according to the disputed results.

Another candidate in the election, the main opposition leader Mir Hossein Mousavi, 71, is also under house arrest.

Mohammad Taghi Karroubi voiced alarm over his father's health on Thursday after two photographs surfaced on pro-government websites showing Mehdi Karroubi at a beach.

The pictures emerged after Mohammad Karroubi had earlier said his father had been taken to hospital without any family present.

Opposition sources have said the release of the photos was aimed at dismissing concerns about Mr Karroubi's health and that it was not clear when the pictures were taken.

''They have held my father in a 'safe house' belonging to the Intelligence Service denying him sunlight and fresh air for two years now and causing his current heart and lung problems," Mohammad Taghi Karroubi was quoted as saying by Sahamnews, a website close to Mr Karroubi.

Mohammad Taghi Karroubi says that authorities have not shown him the doctors' report after they examined his father.

Iranian authorities have said that they would have dealt with Mr Karroubi and Mr Mousavi much more harshly but were held back by Iran's Supreme Leader, Ayatollah Ali Khamenei, who allegedly took a more cautious approach suggesting that a house arrest of the duo would suffice.

The election of Hassan Rouhani to the presidency raised speculation that Ayatollah Khamenei may lift the house arrests in a gesture of goodwill to Iran's revitalised reform movement which are lobbying behind the scenes for him to do so.

President-elect Rouhani said he will work towards lifting the house arrest. ''It is not difficult to create conditions in the country in the coming year so that not only are they released but that those who are held in prison over the 2009 events too are released as well'', he said prior to the election.

Supporters of Ayatollah Khamenei in both the parliament and judiciary have asked Mr Rouhani not to choose his cabinet and associates from those involved in ''sedition'', a reference to the post-2009 election unrest.