Syrians in "leadership positions" who may be responsible for war crimes have been identified, along with units accused of perpetrating them, UN investigators say, Al Jazeera reported.
Both government forces and armed rebels are committing war crimes, including killings and torture, spreading terror among civilians in a nearly two-year-old conflict, they said on Monday.
The investigators' latest report, covering the six months to mid-January, was based on 445 interviews conducted abroad with victims and witnesses, as they have not been allowed into Syria.
The independent team, led by Brazilian Paulo Pinheiro, called on the UN Security Council to "act urgently to ensure accountability" for grave violations, possibly by referring the violators to the International Criminal Court (ICC) for prosecution.
"The international community, and the UN Security Council, must take the decision to refer this to justice," Carla del Ponte, a former UN prosecutor and a member of the commission, said.
"We suggest the International Criminal Court."