A hardline Iranian cleric on Friday called for the execution of “rioters” in the latest sign of the authorities' determination to stamp out opposition to the June 12 presidential election. Iran's top legislative body, the Guardian Council, said it had found no major violations in the election, which it called the “healthiest” vote since the 1979 Islamic Revolution. The council had already rejected a call for the annulment of the vote by moderate former Prime Minister Mirhossein Mousavi, who has led mass protests since he was declared a distant second in the election behind incumbent President Mahmoud Ahmadinejad. “I want the judiciary to ... punish leading rioters firmly and without showing any mercy to teach everyone a lesson,” Ahmad Khatami told worshippers at Tehran University. Iranian state television said on Thursday eight Basij militiamen were killed by “rioters” during the protests. State media previously said 20 people were killed in the marches. Iranian authorities have accused Mousavi of being responsible for the bloodshed, while the moderate former prime minister says the government is to blame. Khatami, a member of the Assembly of Experts, said the judiciary should charge the leading “rioters” as being “mohareb” or one who wages war against God. “They should be punished ruthlessly and savagely,” he said. Under Iran's Islamic law, punishment for people convicted as mohareb is execution. Mousavi's supporters plan to release thousands of balloons on Friday with the message: “Neda you will always remain in our hearts,” in memory of the young woman killed last week who has become an icon of the demonstrations. The authorities have used a combination of warnings, arrests and the threat of police action to drive large demonstrations off Tehran's street since Saturday with small gatherings dispersed with tear gas and baton charges. Seventy professors were detained after meeting Mousavi and his campaign manager was among many arrested. The professors were released on Thursday. The 12-man Guardian Council's statement leaves little scope for more legal challenges, short of an attack on the position of Supreme Leader Ayatollah Ali Khamenei, who has expressed strong support for Ahmadinejad. Former president Akbar Hashemi Rafsanjani, a Mousavi ally, chairs the Assembly of Experts, which has the constitutional power to depose Khamenei. The assembly has never tried to do so and Rasfanjani is seen as unlikely take such a radical step.