Tehran - Iran on Sunday executed 12 people convicted of drug trafficking and other charges, the semi-official Mehr news agency reported.
Seven people had been charged with drug smuggling and the other five with kidnapping, rape, murder and armed robbery.
The convicted drug traffickers were executed early on Sunday in the central province of Fars inside a prison compound, while the other five were publicly hanged to serve "as a deterrent for would-be felons", Mehr said.
The report gave only the initials of some defendants.
Iran is frequently criticised by human rights groups for maintaining one of the world's highest prisoner execution rates.
For drug-related offences alone, it put 488 people to death in 2011, the Amnesty International reported last month. Iran denies violating human rights in this case, saying its chosen form of justice leads to less crime.
Iran is a key transit route for narcotics smuggled from neighbouring Afghanistan, which produces more than 90% of the world's supply of opium.
In recent years, Iran has received international assistance, including from several European countries and the United Nations, to help stem the drug flow across its borders.
Murder, adultery, rape, armed robbery, drug trafficking and apostasy - the renouncing of Islam - are all punishable by death under Iran's shari'ah law practiced since the 1979 Islamic Revolution.