An international human rights group said defectors from Syrian government forces have described how they received and acted upon orders to shoot protesters during anti-regime demonstrations across Syria.
Human Rights Watch says several Syrian soldiers have described taking part in the shooting and wounding of dozens of protesters, as well as in arbitrary detentions of hundreds.
In a report, the New York-based group cites some of the defectors as saying that if they had refused to obey orders, they could have been shot themselves.
Damascus has used a mix of fierce violence and tentative promises of reform to try subdue a 16-week uprising against the authoritarian regime.
Activists say 1,600 civilians and 350 security forces have been killed in four months of violence.