The UN human rights human rights chief, Navi Pillay, has warned armed opposition groups in Syria that executions and unlawful killings may amount to war crimes.

The warning comes as reports emerge that there have been a succession of mass executions in northern Syria.

The UN human rights office says these executions are in violation of international human rights and humanitarian law.

UN Radio’s Patrick Maigua asked Rupert Colville, spokesperson for the UN High Commissioner for Human Rights in Geneva about these executions in Syria.

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