Ganji, jailed in 2000 after writing a series of articles linking senior officials to the murder of political dissidents, was hospitalized in July when his health deteriorated due to a hunger strike aimed at pressuring authorities to release him.

The outspoken reporter, whose plight brought comments of outrage and concern from the United States and European Union, eventually called off his hunger strike after more than 60 days last month.

"Akbar Ganji was released from hospital yesterday and returned to the prison," Karimirad told the official IRNA news agency.

Ganji's wife has said he only ended his fast after receiving assurances from judiciary officials that he would be allowed to go home.

Iran says it considers EU and U.S. calls for Ganji's release as meddling in its internal affairs.

Ganji's lawyer Shirin Ebadi, winner of the 2003 Nobel Peace Prize, told Reuters her client should have been freed from prison long ago on parole since he has completed almost all of his six-year term.