The UN human rights chief is condemning Iran's execution of a woman convicted of murdering her husband five years ago when she was 17 years old.

The office of the United Nations High Commissioner for Human Rights Michelle Bachelet said on October 5 that Zeinab Sekaanvand Lokran had insisted she was coerced into confessing to the 2012 murder and she was beaten by police after her arrest.

Moreover, it said, her claims of being a victim of domestic violence were not adequately considered during her trial, and she was not allowed access to a lawyer until her final trial session, when she recanted the confession that she made under duress.

Sekaanvand was executed on October 2 after her family was given only one day's notice to pay a last visit and "despite a number of appeals from UN Special Rapporteurs and the UN Secretary-General," the UN said.

“The sheer injustice in the case of Zeinab Sekaanvand Lokran is deeply distressing,” Bachelet said. “The serious question marks over her conviction appear not to have been adequately addressed before she was executed. The bottom line is that she was a juvenile at the time the offense was committed and international law clearly prohibits the execution of juvenile offenders."

Bachelet called on Iran's government to honor two international treaties it signed requiring nations to end use of the death penalty against juvenile offenders.

Dozens of other convicted juvenile offenders reportedly remain on death row in Iran, which has already executed at least five juvenile offenders so far this year. The UN rights office opposes the death penalty in all cases.

