Iran's powerful Revolutionary Guard said Sunday that opposition leader Mirhossein Mousavi, a defeated presidential candidate and a former president should be tried for inciting unrest after a disputed presidential poll. The June 12 presidential election plunged Iran into its biggest internal crisis since the 1979 Islamic revolution, exposed deepening divisions in its ruling elite and set off a wave of protests that left 26 people dead. “If Mousavi, (defeated candidate Mehdi) Karoubi and (former president Mohammad) Khatami are main suspects behind the soft revolution in Iran, which they are, we expect the judiciary ... to go after them, arrest them, put them on trial and punish them,” said Yadollah Javan, a senior Guard commander, the official IRNA news agency reported. Protests gripped Tehran and other cities after the vote, which moderates say was rigged to secure the re-election of President Mahmoud Ahmadinejad, but officials say it was the “healthiest” vote in the past 30 years. State media say at least 26 people were killed and hundreds arrested in post-election violence. Authorities say some 200 post-election protesters remain imprisoned, including senior pro-reform politicians, journalists, activists and lawyers. Iranian prosecutor Qorbanali Dorri-Najafabadi said all necessary legal measures would be taken against those “who had violated the law” in Kahrizak, the Etemad-e Melli newspaper reported. Leading moderates including Mousavi and Khatami have called for the immediate release of detainees, saying their confessions were made under duress. Mousavi and Karoubi say Ahmadinejad's next government will be illegitimate, defying Khamenei, who formally endorsed Ahmadinejad last Monday. A group of hardline lawmakers plans to file a complaint against Mousavi for being “the driving force behind the voter turmoil”, Iranian media reported. Such a move may trigger street protests. Ahmadinejad was sworn in by parliament last Wednesday. He said Saturday that he will submit his new cabinet line-up to parliament toward the middle of August.