Iran has carried out a mass execution of 12 inmates at a prison in the southeast part of the country, an NGO said on Tuesday, as concern grows over the rising number of executions in the Islamic republic.

The 11 men and one woman, convicted either on drug-related or murder charges, were hanged on Monday morning in the main prison of Zahedan in Sistan-Baluchestan province close to the borders with Afghanistan and Pakistan, Norway-based Iran Human Rights (IHR) said.

They were all members of the Baluch ethnic minority who mainly adhere to the Sunni strain of Islam rather than the Shiism that is dominant in Iran, it added.

Of the 12, six were sentenced to death for drug-related charges and six were sentenced for murder. None of the executions had been reported by domestic media or confirmed by officials in Iran, it said.

The woman who was executed, identified only by her surname Gargij, was sentenced for the murder of her husband and arrested in 2019, it said.

Activists have long expressed concern that executions in Iran disproportionately target members of Iran's ethnic and religious minorities, notably Kurds in the northwest, Arabs in the southwest and Baluch in the southeast.

"Data gathered by Iran Human Rights shows that Baluch prisoners accounted for 21% of all executions in 2021, while only representing 2-6% of Iran's population," IHR added.

There has also been concern over a recent upsurge of executions in Iran, as the country's leaders are confronted with protests over the increase in prices for basic goods.

According to IHR, at least 333 people were executed in Iran in 2021, a 25% increase compared with 2020.

Amnesty International, in its annual report on use of the death penalty worldwide, said executions in 2021 rose by 28% in Iran compared to the previous year to 314 but warned that the figure was likely an underestimate.

"Death sentences were used disproportionately against members of ethnic minorities for vague charges … and as a tool of political repression," Amnesty charged. (Reuters: Excluding headline)

•The flag of Iran waves in front of the International Center building with the headquarters of the International Atomic Energy Agency, IAEA, in Vienna, May 24, 2021

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