Rights groups have called on Iran to halt the execution of a man for a murder committed while he was still a child. Hossein Shahbazi is due to be hanged on Monday following the death of a teenager during a group fight when he was 17. He would be the first person to be executed this year in Iran after committing a crime as a minor, according to Amnesty International. Several others involved in the fracas were arrested and provided confessions but have not been sentenced to death, say campaigners. Amnesty International said the conviction should be quashed and Shahbazi, now aged 20, given a retrial without the possibility of a death penalty. He was arrested in December 2018 and questioned at a police detention centre without access to a lawyer or his family for 11 days in Shiraz, Fars province, the rights group said. He was then moved to a juvenile detention centre and held there for several more days before his mother was allowed to visit. He had bruises on his face and had lost weight. Shahbazi was sentenced to death in January 2020 and is currently held in Adelabad prison in Shiraz. The conviction was based in part on confessions that he said he made after being tortured and subjected to other ill treatment at the detention centre. Amnesty International has called on the EU and UN to bring pressure on Iran before Monday. “Using the death penalty against someone who was a child at the time of the crime is prohibited under international human rights law and violates Iran’s international obligations,” said Diana Eltahawy of Amnesty International. “Going ahead with this execution would be an abhorrent assault on children’s rights and would make an absolute mockery of justice.” Shahbazi's conviction was upheld by Iran’s supreme court in June last year when it was acknowledged he was under 18 at the time of the crime. After the campaign was launched to stop his execution, prison guards told Shahbazi that they would speak to the victim’s family to ask them for a pardon. Death sentences can be avoided in Iran if the convicted killer pays the bereaved family a compensation. The penalty can then be replaced by short prison terms. Campaigners say the judiciary should take the lead and not impose death sentences on juveniles, rather than rely on family mercy. Iran continues to use the death penalty for crimes committed by people under the age of 18, despite signing a UN agreement banning the practice in 1968. The International Covenant on Civil and Political Rights says "the sentence of death shall not be imposed for crimes committed by persons below 18 years of age and shall not be carried out on pregnant women". Amnesty International said that at least three juveniles were executed in 2020 and scores of others remain on death row. Iran executed 246 people last year, the second highest number for any country behind China.