Algerian former defence minister Khaled Nezzar, seeking medical treatment in Switzerland, was arrested on Thursday, the ATS news agency reported late Friday, confirming a report by the Swiss Association Against Impunity (TRIAL).

The investigation was prompted by complaints by two victims stemming from Algeria's 1990s civil war pitting Islamist extremists against government forces, submitted by TRIAL, a spokesman for the prosecutor's office said.

The 74-year-old retired general attended a hearing Friday along with the two plaintiffs. Algeria's defence minister from 1990 to 1994, Nezzar was considered one of the regime's most powerful figures, according to TRIAL. "The winds of the Arab Spring have reached Switzerland," said TRIAL's director Philip Grant.

However, TRIAL criticised the Swiss prosecutor for releasing Nezzar "on the basis of a promise to attend" future hearings, saying he should have been kept in protective custody as he presented a high flight risk.