HUMAN rights campaigners in Syria held a sit-in protest on Wednesday demanding justice for four activists who were forcibly disappeared in 2013 — and whose fate remains one of the most haunting mysteries of the 13-year civil war.

On December 9 2013, gunmen stormed the Violation Documentation Centre in Douma, north-east of Damascus, and took Razan Zaitouneh, her husband Wael Hamadeh, Samira Khalil and Nazem Hammadi.

Outspoken and defiantly secular, Ms Zaitouneh was one of Syria’s best known human rights activists. She chanted in protests against then president Bashar al-Assad but was also unflinching in documenting abuses by rebels fighting to oust him.

There has been no sign of life nor proof of death since she and her colleagues were abducted.

Since the overthrow of Mr Assad on December 8, protests have erupted across Syria demanding information about thousands of people who went missing under his rule.

The new leadership under Islamist group Hayat Tahrir al-Sham (HTS), which ousted the Assad government, has maintained a neutral stance towards accusations against various armed groups that they forcibly disappeared activists. At the same time, HTS has aligned with activists in their efforts to uncover the truth and seek justice.

“We are gathering here to remind the world of their case,” Yassin Haj Saleh, Ms Khalil’s husband, said, adding that the disappearance of activists represented “the deepest wounds” of Syria’s conflict.

“This is the first opportunity that allows us to be in Douma and in front of the place that they were kidnapped from, to speak up about the case, taking advantage of the political change that took place in the country.”

Mr Saleh said they had repeatedly appealed to various armed groups for co-operation in finding the four activists in the years before Mr Assad’s fall but had been met with silence.

Strong clues had pointed to the Army of Islam, the most powerful rebel faction in Douma at the time, as the perpetrator.

The group, made up of religious zealots who were pushing out other rebels and imposing strict Sharia rules, long denied involvement. Army of Islam official Hamza Bayraqdar told reporters in 2018 that they had brought Ms Zaitouneh to Douma to protect her from Mr Assad’s government.

The Army of Islam repeatedly blamed the Assad government, along with the Nusra Front — an al-Qaida-linked group founded by the current HTS leader — for his wife's disappearance, Mr Saleh said.

Ms Zaitouneh was a prominent human rights lawyer and founder of the Violation Documentation Centre. She also helped organise networks of campaigners such as the Local Co-ordination Committees, an umbrella network made up of activists who organised protests as part of the Syrian uprising.

Several of those who spoke to reporters in 2018 said the Army of Islam saw Ms Zaitouneh documenting abuses as a threat and resented her local administration plan as an encroachment on their power.

She received a series of threats that friends and activists said traced back to the Army of Islam.

The Army of Islam was forced to move north in 2018 after the Assad government retook Douma, leading to the group’s weakening and disintegration. Hopes that Ms Zaitouneh and her colleagues would emerge among released prisoners during that time were dashed.

Today, the Army of Islam remains an armed faction backed by Turkey. It did not fight alongside the other Islamist factions that led the offensive against Mr Assad and remains excluded from the HTS-led Syrian leadership.

Recently, an Army of Islam delegation met HTS leader Ahmad Sharaa (formerly Abu Mohammed al-Julani) to explore its integration into the new Syrian system, but no agreement has been reached.

Protesters on Wednesday held banners openly accusing the Army of Islam and reading “freedom” in English and “traitor who kidnaps a revolutionary” in Arabic, alongside posters of the four missing activists.

Mr Saleh described the plight of the disappeared as uniquely painful, saying: “Those who die are mourned, but the forcibly disappeared are forbidden from both living and being mourned.”

Their bodies must be found, he said, adding: “For Syria to heal, truth and justice must prevail.”

Wafa Moustafa, whose father was forcibly disappeared separately in 2013, also attended the protest.

“Justice in Syria cannot be limited to those detained by the Assad regime,” she said.

“For many years, other factions controlled parts of Syria and committed similar crimes of detention, torture and killing.

“If justice does not include all victims, it will remain incomplete and threaten Syria’s future.”