Iran has executed a female victim of domestic and sexual violence who was convicted of killing her husband when she was a minor, according to Amnesty International.

The execution of Zeinab Sekaanvand is "profoundly unjust and shows the Iranian authorities' contempt for the right of children to life," the London-based human rights watchdog said on October 2.

A statement said the 24-year-old was hanged early in the day in Urumieh central prison in West Azerbaijan province.

An ethnic Kurd, Sekaanvand was 15 when she married her husband, according to Amnesty, and she was sentenced to death in October 2014 following a "grossly unfair trial" for allegedly stabbing him to death.

Philip Luther, Amnesty International's research and advocacy director for the Middle East and North Africa, said she "sought help many times from the authorities about her violent husband and alleged that her brother-in-law had raped her repeatedly."

Instead of investigating the allegations, Iranian authorities "consistently ignored her and failed to provide her with any support as a victim of domestic and sexual violence," Luther added.

He also called Sekaanvand's execution "a sickening demonstration of the Iranian authorities' disregard for the principles of juvenile justice and international human rights law."

A spokeswoman for EU foreign-policy chief Federica Mogherini said that death-penalty sentences and executions for crimes committed by persons below the age of 18 are "inconsistent with Iran's international obligations under the International Covenant for Civil and Political Rights and the Convention on the Rights of the Child."

Maja Kocijancic also noted that Sekaanvand was "a child bride and reportedly a domestic abuse victim" who "maintained her innocence and...retracted her confession, claiming that it had been the result of torture."

Amnesty International urged Iran to establish a moratorium on executions, commute all death sentences, and prohibit the use of the death penalty against people below the age of 18 at the time of the crime.

Iran is one of the world's leading executioners. Amnesty International said in April that 507 people were executed in the country last year, including at least five juvenile offenders.

With reporting by Rikard Jozwiak in Brussels