The U.N.'s human rights expert on Iran is condemning the Islamic Republic's reliance on stoning as a form of capital punishment, citing that as just one of a number of "deeply troubling" Iranian rights violations, many of which are "systemic in nature," according to a report circulating among U.N. delegations.

Ahmed Shaheed, the Geneva-based U.N. Human Rights Council's special rapporteur on Iran, also called for an "extensive, impartial and independent investigation into the violence in the weeks and months that followed the presidential election of 2009," when pro-democracy protesters surged into the streets to denounce the election of President Mahmoud Ahmadinejad as bogus and rigged.

Shaheed also "reiterates his call for the immediate release of all political prisoners and prisoners of conscience," according the report, which The Associated Press obtained Thursday.

The document will be the basis for a General Assembly resolution critical of Iran's human rights violations, which will probably be voted on in December.

Shaheed reported that at least 150 journalists have fled Iran since the 2009 elections, and some reports put the number as high as 400.

Iran detained more journalists than any other nation last year, according to his report, and to the New-York based rights group Committee to Protect Journalists, which counted 179 writers, editors and photojournalists jailed in Iran in December 2011.

Half of them spent time in solitary confinement, 42 percent were sent into exile in 2010-2011, and half were serving sentences ranging from 6 months to 19 ½ years on charges such as "working with hostile governments", "propaganda against the state", and "insulting religious sanctities," Shaheed wrote.

As the report was being prepared last March, Iran's Foreign Ministry said Shaheed was building it on statements by "terrorists." The term "terrorist" is an apparent reference to the Mujahedin-e Khalq, a small exile group that until recently was listed by the U.S. as a terrorist organization. The MEK says it has renounced violence, and also represents a very small fraction of the opposition to the government in Tehran.

Iran does not allow Shaheed entry to the country to conduct his research, and regards his reports as punitive. Shaheed said he followed 124 cases of human right violations for his report and conducted 99 interviews with individuals who were inside and outside Iran between February and June.

Officials at Iran's U.N. mission did not immediately return calls seeking comment on Shaheed's completed report.

Iran is now cracking down on Internet users, with Shaheed reporting that 19 bloggers and Internet commentators are currently detained in the Islamic Republic of Iran. Four of those detained, Vahid Asghari, Ahmad Reza Hashempour, Mehdi Alizadeh Fakhrabad and Saeed Malekpour, were sentenced to death in January 2012. "

They were accused of "enmity against God" and "corruption on earth"; collaboration or engagement with foreign governments; insulting leaders of the country; and launching and maintaining pro-opposition websites.

Another blogger, "Sakhi Righi, was issued the harshest prison sentence ever served to a blogger in the country — 20 years — for 'publishing false Information' and committing 'acts against national security,'" Shaheed said.

Iran is expanding its crackdown by targeting websites deemed to promote "terroristic, espionage, economic or social Crimes, he said. "This includes websites that allegedly possess pornographic content, insult Islam or Government officials, proselytize unrecognized religions, or establish anti-government political groups."

In two dozen interviews, Shaheed said he had learned of Iranian human rights defenders "being arrested and held incommunicado in solitary confinement for periods ranging from several weeks to 36 months, without charge or access to legal counsel."

"Most of them also reported that they were subjected to severe physical torture during interrogations, which were aimed at coercing confessions or soliciting information about other human rights defenders and human rights organizations," he said.

"Methods employed reportedly included severe beatings with batons and other objects, mock hangings, electrocution, and actual rape. Other forms of psychological torture allegedly included sleep deprivation, denial of food and/or water, and threats of arrest, detention, rape or murder of family members. Several victims also reported being drugged with hallucinogens," Shaheed reported.