The Iranian foreign ministry summoned the Swedish chargé d'affaires in Tehran on Thursday and handed him a note of protest over a Swedish court sentence against the former Iranian official Hamid Noury, Iran's Arabic-language television network Al Alam reported.
A Swedish court sentenced Noury to life in prison for his part in the mass execution and torture of political prisoners in the 1980s.
Noury, 61, was convicted of a "serious crime against international law" and "murder", the Stockholm district court said in a statement.
According to the prosecution, Noury was an assistant prosecutor in a prison near Tehran at the time of the events.