Iranian authiorities have executed a prisoner associated with an exiled opposition group, the group's website has said.

A statement from the People's Mujahideen Organisation of Iran, and a report from the semi-official state news agency Fars, said that Gholamreza Khossravi was hanged on Sunday. 

"Gholamreza Khossravi, who had spent 12 years of his life in mullahs' regime dungeons and over 40 months in solitary confinement, was sentenced to death only for his support for People's Mojahedin of Iran," the group said. 

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Khossravi was sentenced to death in 2010 for providing photographs of the country's military facilities and financial aid to the exiled opposition group.

He was also accused of helping to recruit members for the group, the AP news agency reported, quoting the Iranian state news agency IRNA.

It said Khossravi was arrested in 1997, having been previously held between 1981 and 1986.

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The PMOI began fighting to overthrow the Islamic Republic shortly after the 1979 revolution, but renounced violence in 2001.

"The brutal and inhumane execution of Mr Gholamreza Khosravi shows nothing but the weakness, prostration and incompetence of the kneeling Velayat Faqih regime," the PMOI said.

On Saturday, the human rights group Amnesty International said the execution would be a breach of domestic and international law because Khossravi did not receive a fair trial.

Source: AP