Journalist Akbar Ganji, who has just been released from jail, has become a symbol of resistance for Iran's reformists.
There have been questions about Akbar Ganji's treatment in prison
The state's most prominent political dissident continued his criticism of Iran's ruling clerics from behind bars.
His case has drawn international concern - and powerful allies.
US President George W Bush and UN Secretary General Kofi Annan are among those who had called for his release.
The former Revolutionary Guard turned reformist was jailed for six years in 2001, over articles linking Iranian leaders with a series of political killings in 1998.
The Intelligence Ministry said "rogue agents" had carried out the killings, but Ganji maintained senior officials were behind them.
His imprisonment came amid a media crackdown by hardliners as the then reformist president Mohammad Khatami appeared to be threatening their power.
Akbar Ganji's wife thought he might never be released
Ganji has continued to write in prison and his letters have been smuggled out and published on the internet.
In 2002 he wrote a Republican Manifesto which laid out plans for a democratic Iran.
Ganji went on hunger strike for about 40 days to demand his unconditional release, a call backed by the US, EU and international human rights organisations.
The Iranian government denied the hunger strike, saying he had been taken to hospital for treatment to his knee.
His family have since expressed concerns about his health.
They say he has low blood pressure and weighs only 49 kg, after - they allege - being denied regular food by the jail authorities.
His wife had said the authorities had pledged never to release her husband unless he withdrew his accusations and apologised to Iran's supreme leader, Ayatollah Khamenei.