The leader of Jundallah, an Iranian Sunni Muslim group that has been engaged in an insurgency against the Iranian government for years, has been hanged in public in Tehran, the capital.
Abdulmalek Rigi, who was executed on Sunday, was the government's public enemy number one. He was accused of being behind several attacks since 2005 that have killed more than 150 people, including security personnel and civilians.
Jundallah says it is fighting for the rights of Sunnis, who they claim are discriminated against and oppressed in the Shia dominated country.
Al Jazeera's Dan Nolan reports.