A former aide to Iranian presidential candidate Mehdi Karroubi said that the supreme leader of Iran must answer for his stance on the Iranian prison system.

Radio Zamaneh, a Persian news service in the Netherlands, reported that Issa Sakarkhiz, who campaigned for Karroubi in 2009, said he was considering pressing charges against Iran's Supreme Leader Ali Khamenei for "remaining silent in the face of detainee torture."

It has been reported that the campaigner and journalist was arrested by Iranian authorities in northern Iran in July 2009. Amnesty International said following his arrest that he was "at risk of torture or other ill-treatment" while in detention.

His arrest followed the July publication of an article on the news Web site Rooz criticizing the supreme leader.

He was "beaten and tortured" by security officers during his arrest in July and blamed Khamenei for trampling the constitution and deviating from the path of justice, he said.

It has further been reported that Political violence followed contested presidential elections in June 2009. Iranian authorities responded with a massive security crackdown that left several opposition figures dead.