The report is the result of interviews with more than 200 victims, witnesses and army defectors by members of an independent panel. Investigators were not allowed to enter Syria themselves, however, the BBC reported.
Their findings contain allegations of serious violations of human rights, said the Washington Post:
The report, by the Independent International Commission on Syria, documents credible evidence that high-ranking officers consistently, across the country, issued orders to shoot at civilian homes and unarmed protesters, and records evidence of systemic torture and sexual violence against those in custody.
Soldiers said they were ordered to shoot protesters without warning, and beaten when they disobeyed. Detainees said they were subjected to electric shock torture, threats against them and their families, orders to worship President Bashar al-Assad instead of their god, and rape, including of young boys, reported Reuters.
At least 256 children have been killed by security forces during months of unrest, the report said, among an estimated total of 3,500 deaths.
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Damascus blames armed terrorist gangs for provoking the violence. Yet the panel said the majority of civilians were killed during peaceful demonstrations, and said security forces enjoyed "systematic impunity" for their crimes:
"The sheer scale and consistent pattern of attacks by military and security forces on civilians and civilian neighbourhoods and the widespread destruction of property could only be possible with the approval or complicity of the state."
The panel is calling on the Syrian government to halt the abuses immediately and bring the perpetrators to justice.
President al-Assad has so far resisted international pressure to implement a peace deal. The Arab League has suspended Syria and on Sunday approved unprecedented economic sanctions against it, while the European Union has imposed its own sanctions on individual Syrians accused of aiding the repression of protesters.
Some fear this latest report will have no more effect than previous measures. Peter Harling of the International Crisis Group told the Washington Post:
"The regime is facing huge international pressure. The West has more or less unanimously turned against it, it has no support from the Arab countries or the Arab streets and still it shows no sign of compromise. It has passed the point of compromise."
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