The Syrian regime has executed up to 13,000 people in secret mass hangings carried out in the basement of a military prison near Damascus, Amnesty International has said.
A report by the human rights group alleges that Bashar al-Assad's security forces carried out "a calculated campaign of mass hangings and extermination" at Saydnaya, a military prison outside the capital.
"Saydnaya Military Prison is where the Syria state quietly slaughters its own people," the report states.
"The victims are overwhelmingly ordinary civilians who are thought to oppose the government."
Prisoners are kept in the "red building" of the hulking three-winged prison until they are taken before a military court in Damascus.