Iran's supreme leader, Ayatollah Ali Khamenei, has been urged to provide a written explanation for Boroujerdi's continued detention or set him free. Photograph: Morteza Nikoubazl/Reuters
An imprisoned Iranian cleric who fell foul of the authorities after advocating the separation of religion and state is in poor health condition, activists have warned.
Ayatollah Hossein Kazemeyni Boroujerdi was sentenced to 11 years in jail in June 2007 following a trial behind closed doors that found him guilty of 30 charges including acting against national security and having links with anti-revolutionaries and spies.
His supporters say the charges stemmed from his opposition to the involvement of religious clerics in politics and his public criticism of the country's supreme leader, Ayatollah Ali Khamenei. Boroujerdi, an outspoken Shia cleric has repeatedly called the concept of political leadership by the clergy unlawful and has described Tehran's regime as a "religious dictatorship".
Boroujerdi was arrested along with hundreds of his followers in Tehran in October 2006 after clashes between security officials and his supporters.
The 53-year-old scholar, who is currently held in Tehran's Evin prison in a ward designated for dissident clerics, was initially given a death sentence before an appeals court reduced it to 11 years in jail. He was found guilty of insulting the supreme leader, spreading propaganda against the regime and moharebeh or waging war against God, a charge that carries the death penalty under Iranian law.
Boroujerdi is the son of a prominent ayatollah who refused to back Rouhollah Khomeini in his years as the founder of the Islamic revolution in 1979.
According to Amnesty International, Boroujerdi has been subjected to torture and ill-treatment while in prison and suffers from Parkinson's disease, diabetes and high blood pressure. His health is believed to have worsened in recent weeks.
"In Iran, people are fed up with a religious regime and because of that unfortunately people do not pay enough attention to the fate of a religious figure who is put in jail for his views," said Maryam Moazen, an activist who has campaigned to highlight Boroujerdi's plight. "Unlike clerics who are associated with officials in power, Mr Boroujerdi had been very critical of the regime's violation of human rights."
According to Moazen, Boroujerdi has been kept incommunicado but has had intermittent access to his family. "People associated with Boroujerdi including his family have also been persecuted by different means such as being arrested or interrogated," said Moazen, who was among the followers arrested for their support for the cleric.
He said Boroujerdi is also suffering from heart problems and permanent shaking of his legs and hands.
A group of prominent journalists and human rights activists have written a public letter raising alarm over Boroujerdi's situation. "Kazemeini Boroujerdi has been subjected to the most inhumane forms of physical and psychological torture to force him into signing a statement renouncing his beliefs," said the letter, according to Iran's Human Rights Activists News Agency (HRANA).
"Ayatollah Khamenei, as supreme leader and head of the special court of clergy [which found Boroujerdi guilty], has moral, judicial and constitutional duty to provide a written explanation or set him free."
Iran's embassy in London could not be reached for comment.