Since the conflict in Syria began in 2011, the government has been accused of “forcibly disappearing” tens of thousands of people, many of them peaceful protesters who later died or were killed in detention.
Armed opposition groups have also been responsible for the disappearance of activists in areas they control, but on a much smaller scale.
Among them was rights activist Razan Zaitouneh – one of the faces of the uprising against President Bashar al-Assad.
Zaitouneh, who founded the Violation Documentation Centre, was wanted by the Syrian government for her role in peaceful protests calling for its downfall.
Her centre kept track of atrocities and abuses committed not just by the government but the armed opposition, too.
In December 2013, Zaitouneh, along with three of her colleagues, including her husband, disappeared after being taken at gunpoint from their office in Douma.
Back then, the town on the outskirts of the Syrian capital, Damascus, was surrounded by government forces but it was under the control of the opposition.
Fellow activists say Jaish al-Islam (Army of Islam), arguably the most powerful group at the time, saw 36-year-old Zaitouneh as a threat. She promoted a civil administration and a secular state which were not in line with the group’s ideology.
“We, the Violations Documentation Centre in Syria, are sure the Army of Islam kidnapped them,” said Mazen Darwish, a Europe-based Syrian lawyer and a colleague of Zaitouneh.
“We have proof that Razan was in their jails and under their direct supervision. This was until the beginning of 2017 as we were able to trace her movements. Regrettably after the beginning of 2017, information was cut and we have no knowledge about Razan.”
Jaish al-Islam, however, denied any involvement or knowledge of the kidnap.
“Jaish al-Islam was not the only faction in Douma at the time,” Hamza Bayraqdar, a spokesperson for the group said.
“There was in the entire region forces from the Martyrs of Douma, forces of the Ghouta rising, the Islamic Union of the Levant and even the Nusra Front were present.”
Earlier this year, Jaish al-Islam was forced to surrender besieged Douma to government forces.
Before leaving the area, Jaish al-Islam began releasing detainees from the Tawbeh prison. Witnesses say Razan and her colleagues were held there.
They have not been found.