He said on Thursday, new statistics would be published shortly on the number of victims in the Syrian conflict and predicted that the updated death toll "will be well over 200,000".
He added the UN mission to Iraq was also collecting information on the number of deaths from the conflict in northern Iraq, where the radical Islamic State (IS) terrorist group has seized vast areas of Iraqi territory, just as it has done in Syria.
The UN High Commissioner described the IS as a genocidal movement, which used the internet and social media to brainwash and recruit people from all over the world.
Al-Hussein explained that the radical group violated human rights with the worst abuses and crimes in Iraq and Syria. It committed murder, torture and rape, he said. Its definition of justice was killing.
He urged the UN Security Council to transfer the case of Syria and Iraq to the International Criminal Court so they can investigate the atrocities that are taking place in the region.