Despite the high-profile and shocking nature of the so-called "Islamic State" and its push through Iraq and Syria, the Syrian regime of Bashar al-Assad is still responsible for the majority of war crimes being committed in that country, according to the author of a special UN report into the Syrian civil war.
With no end in sight to the three and a half year conflict, a special United Nations panel presented its findings Tuesday in a depressing 17-page report.
Paulo Sergio Pinheiro, who led the four-person panel, said he had "run out of words to depict the gravity of the crimes committed inside Syria."
He noted that the Islamic State, which recently beheaded three western hostages James Foley, Steven Sotloff and David Haines, has similarly subjected countless other Syrian civilians to similar public executions and brutal punishments.
The report is based on eyewitness testimonies from Syrians interviewed by the team, hailing from across the country.
Pinheiro also highlighted the mass-killings of prisoners of war - as occurred after IS's recent capture of Tabqa airbase in northern Syria - as well as of dissenters and political opponents.
Women are particularly vulnerable to abuse at the hands of the Islamist terror group, with several already being stoned to death based on accusations of adultery, or publicly flogged for minor offenses such as walking in the street without a male chaperone.
Nevertheless, Pinheiro pointed out that the regime of Bashar al-Assad "remains responsible for the majority of the civilian casualties, killing and maiming scores of civilians daily."
Civilians are being slaughtered at the hands of the regime in a variety of ways - from indiscriminate shelling, air raids and "barrel bombings", to shootings and summary executions at the hands of soldiers and pro-government militiamen.
Those captured or arrested by the regime were subjected to horrific torture and denied food or water for prolonged periods of time. Female prisoners were regularly raped or otherwise sexually abused.
Pinheiro said that the inaction on the part of major world powers to intervene - via the UN Security Council or otherwise - has helped fuel the conflict. It's most recently "beneficiary", he said, was the Islamic State - but the Syrian government has been able to escape justice for its massacres for longer still.