Iran executed Iranian-German national Jamshid Sharmahd after he was convicted of carrying out terrorist attacks, Iranian state media said on Monday.
Sharmahd, who also holds US residency, was sentenced to death in 2023 on charges of "corruption on earth".
He was accused by Iran of heading a pro-monarchist group accused of a deadly 2008 bombing and planning other attacks in the country.
Sharmahd's arrest was announced in 2020 in an intelligence ministry statement that described him as "the ringleader of the terrorist Tondar group, who directed armed and terrorist acts in Iran from America."
His family disputed the allegations and had worked for years to see him freed.
Based in Los Angeles, the little-known Kingdom Assembly of Iran, or Tondar, says it seeks to restore the Iranian monarchy that was overthrown by the 1979 Islamic revolution. It runs pro-Iranian opposition radio and television stations abroad.