International investigators have submitted a list of Syrian military and political officials suspected of crimes against humanity to the UN's top human rights official, their report said on Thursday.
"The commission has deposited with the High Commissioner (for Human Rights, Navi Pillay) a comprehensive database containing all evidence collected," said the report from an international commission of inquiry.
"Consistent with its mandate, the commission endeavoured, where possible, to identify those responsible with a view to ensuring that perpetrators of violations, including those that may constitute crimes against humanity, are held accountable," added the inquiry, commissioned by the UN Human Rights Council.
The commission documented a widespread and systematic pattern of gross violations committed by Syrian forces, "in conditions of impunity", since March 2011 when the uprising against President Bashar al-Assad's regime erupted.
The report said the Syrian government has "manifestly failed" to protect its people but it also said that it had found instances of gross abuses committed by anti-government armed groups.
The commission regretted the Damascus government did not allow investigators into Syria, nor did it grant its requests to interview government spokesmen.
According to the British-based Syrian Observatory for Human Rights, more than 7,600 have been killed in the 11 months since the uprising began.
"The human rights situation ... has deteriorated significantly since November 2011, causing further suffering to the Syrian people," wrote the commission after conducting 136 interviews since its last report in November.
The commission recommends the initiation of an inclusive political dialogue, bringing together the government and opposition groups.
Both sides should "negotiate an end to the violence, to ensure respect for human rights and to address the legitimate demands of the Syrian people," said the commission.
It suggested that a contact group of countries with diverse positions on the situation should be established to initiate a process leading to such a dialogue.
"Reconciliation and accountability will be achieved only if there are credible consultations with the population, including women and minorities, as well as with victims. Profound political, justice and security sector reforms must also be undertaken," said the commission.