The semiofficial Fars news agency says the militia has sent Iran’s chief prosecutor a letter accusing Mousavi of taking part in nine offenses against the state, including "disturbing the nation’s security."

That charge carries a maximum penalty of 10 years’ imprisonment.

The Basiji are known as the street enforcers of Iran’s supreme leader, Ayatollah Ali Khamenei.

Iran’s regime says 17 protesters and eight Basiji were killed in two weeks of unrest.