Relatives of murder victims held aloft pictures of their loved ones, demanding the execution of imprisoned suspects, while human rights groups in the Palestinian territory marked World Day against the Death Penalty.
“The death penalty is Islamic law – implement it against all criminals,” one banner read.
On October 2, Hamas hanged Hani Abu Aliyan, a 28-year-old who had been convicted for murder.
“The death penalty is fair, it’s a balanced outcome,” said Shayma Tilbani, 17, whose brother was killed at his home in an attempted burglary in August.
“The NGOs want to stop the criminals getting executed, but even life in prison is not the right punishment. We want a punishment based on the Koran,” she told AFP.
Mohammed Shurab, spokesman for Gaza's "Families of the Victims" movement, urged “the government in Gaza led by (prime minister) Ismail Haniya to continue carrying out the death sentence against those who are killing our sons."
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But speakers at the conference said the death penalty went against both international humanitarian law and the principles of Islam.
“Islam doesn’t allow the death penalty or the killing of anyone,” said Suleiman Awda, a lecturer in Islamic law at Gaza’s Al-Azhar University. “It is a religion of forgiveness.”
UN human rights delegate Pradeep Wagle expressed concern over Hamas’s use of capital punishment, warning in particular of the dangers of mistakenly sentencing a suspect.
“Human failure is always possible irrespective of how developed a justice system is and there is always the possibility of executing innocent people in any justice system,” he said.
Saeed al-Madhun, from the UN High Commissioner for Human Rights, warned it was “not possible to correct a mistake… There’s no going back once the death penalty has been carried out.”
Last week's hanging was the first time since July 2012 that Hamas has carried out capital punishment for murder.
But on June 22, the Islamist movement hanged two men accused of collaborating with Israel.
Under Palestinian law, collaboration with Israel, murder and drug trafficking are all punishable by death.
Hamas has executed 17 people since taking over Gaza in 2007, according to the Palestinian Centre for Human Rights.