Rights groups say the figure could be as high as 20 and that the convictions may have been based on forced confessions
Iran has executed a group of 20 "terrorist" Sunni prisoners suspected of attacks on security forces, drawing condemnation from rights groups which said the convictions may have been based on forced confessions.
State news agency IRNA said members of the Tawhid and Jihad group were executed on Tuesday, but did not give a figure. Rights groups said between 10 and 20 people were killed.
They were convicted of killing two Sunni Muslim clerics, several police and wildlife guards, abducting a number of people and carrying out armed robbery and bombings in Western Iran, IRNA said.
Iranian state television broadcast what it said were the confessions of some members of the Sunni Muslim group, in which they said they targeted both Shi'ite and Sunni clerics whose ideologies they regarded as heresy.
Iran's seven million Kurds make up around 10 per cent of the population. Most live in Kurdistan and other northwestern provinces on the border with Iraq. Many Kurds seek greater rights for their region.
The area has seen increased clashes between kurdish militants and government security forces in recent months.
Iran's intelligence ministry said in a statement carried by IRNA that more than 100 members of the Tawhid and Jihad "terrorist" group had been identified, many of whom had been arrested or killed in clashes since 2011.
The International Campaign for Human Rights in Iran, an independent organisation based in New York, said 20 prisoners had been hanged. It said Iran's Supreme Court had rejected the appeal of one of the convicts, Shahram Ahmadi, against his death sentence despite assertions his confession was made under torture.
Human Rights Watch condemned Iran for what it said was the "mass execution of at least 10 prisoners". Sarah Leah Whitson, HRW's middle east and north africa director, said Iran had executed at least 230 people in 2016.
Iran is one of the world's top executioners, international rights groups say. Amnesty International said Iran executed at least 977 people in 2015.
Iran rejects international criticism of its rights record as politically motivated.
Iran's judiciary said the latest cases had been under deliberation for more than six years to make sure all aspects were investigated and the rights of the accused protected.