Iran's decision to hang media activist Ruhollah Zam on Saturday was an appalling violation of human rights that followed a deeply flawed trial process, UN High Commissioner for Human Rights Michelle Bachelet said in a statement on Monday. "I am appalled at the execution in Iran on 12 December of Ruhollah Zam, activist, and founder of the AmadNews Telegram channel", Bachelet said in a statement. "His death sentence and execution by hanging are emblematic of a pattern of forced confessions extracted under torture and broadcast on state media being used as a basis to convict people. There were, in addition, serious concerns that the apprehension of Zam outside the territory of Iran could amount to abduction and that his subsequent transfer to Iran for trial may not have respected due process guarantees." Bachelet called on Iran's government to immediately free all those detained for exercising their human rights, and to immediately halt the use of the death penalty and "vague national security charges" to suppress independent voices and dissent. She said she condemned the use of the death penalty in all circumstances, saying that it was irreconcilable with human dignity, often arbitrarily used, and wrongful executions could be never be rectified. "Under international human rights law, if applied at all, the death penalty must be limited only to the most serious crimes, involving intentional killing, and after proceedings that fully respect the guarantees of fair trial, appeal and the right to seek clemency — cumulative conditions clearly not met in Ruhollah Zam's case", Bachelet said. In a separate statement, two UN Special Rapporteurs — independent rights experts mandated by the UN Human Rights Council — called Zam's conviction and subsequent hanging, "unconscionable". The statement from Javaid Rehman, Special Rapporteur on the situation of human rights in the Islamic Republic of Iran, and Agnes Callamard, Special Rapporteur on extrajudicial, summary or arbitrary executions, said Zam had been convicted for allegedly "spreading corruption on earth". They said Zam was accused of helping to inspire nationwide anti-government protests in 2017 and revealing damaging accusations about state officials. "It is clear that Ruhollah Zam was executed for expressing opinions and providing information on AmadNews that dissented from the official views of the Iranian government", they said. In January this year, Rehman, submitted a report to the UN Human Rights Council that raised concerns about Zam's case, saying that Iranian television had aired a statement by Zam in which he expressed his "regret" over trusting the Governments of France and other countries. "It has been reported that Zam was persuaded, under false pretenses, to go to Iraq from France, where he had refugee status. In Iraq, he was captured and returned to the Islamic Republic of Iran by the Islamic Revolutionary Guard Corps", the report said. Rehman had recently informed the Iranian government about his serious concerns about Zam's death sentence, the statement said. High Commissioner Bachelet said many activists and protesters had been given long prison terms or the death penalty for exercising their human rights after trials that failed to meet international standards. Those sentences amounted to serious violations under the International Covenant on Civil and Political Rights, including the right to freedom of opinion and expression, and the right to life, she said.