The first man, identified as Malek S. 30, was hanged for trading 1.018 kilos (2.23 pounds) of heroin.

Javad S., 23, went to the gallows for possessing 29 kilos (63.8 pounds) of opium and weapons.

Qasem and Kavoos, both 24, were executed for having 154 kilos (338.8 pounds) of opium and weapons.

The report did not give any extra information.

The hangings bring to at least 102 the number of executions carried out in the Islamic republic so far this year. At least 177 people were executed in 2006, according to an Amnesty International report.

Capital offences in Iran include murder, rape, armed robbery, apostasy, blasphemy, serious drug trafficking, repeated sodomy, adultery or prostitution, treason and espionage.