No group has claimed the four activists' abduction and they have not been heard from since.
Ankara-backed rebels played a key role in supporting Sharaa's Islamist group Hayat Tahrir al-Sham (HTS), which headed a rebel alliance that seized Damascus on December 8, toppling longtime ruler Bashar al-Assad.
The seismic change in Syria is expected to yield deeper Turkish sway just as a change of US administration is raising questions over how long Washington will keep backing the country's Kurdish-led forces.
Assad fled Syria following a lightning offensive spearheaded by the Islamist Hayat Tahrir al-Sham (HTS), more than 13 years after his crackdown on democracy protests precipitated one of the deadliest wars of the century.
Darwish was detained for months by one of the most feared branches of the former government's many-tentacled intelligence services.
Syrians will not miss Assad, a brutal ruler who failed his people.
The offensive, which took just 10 days to sweep across Syria and take the capital Damascus, stunned the world and brought an end to more than a half a century of brutal rule by the Assad clan.
"We would like to see the situation in the country stabilised somehow as soon as possible," Kremlin spokesman Dmitry Peskov told reporters.
"Their human capital, their experience will allow the country to flourish," Bashir said in an interview published Wednesday.
The recent picture of the child all-dolled up and lying dead on the beach had drenched our hearts with tears. He was one of the thousands of refugees who were trying to escape to safety from the civil war raging in the Middle-east.
The Syrian man who survived a capsizing during a desperate voyage from Turkey to Greece buried his wife and two sons on Friday in their hometown of Kobani, returning them to the conflict-torn Syrian Kurdish region they had fled.
From learning the real issues to supporting both large organizations and grassroots efforts alike, here are six concrete ways that you can help during the refugee crisis.
The image of little Aylan Kurdi is hammering home the Syrian migrant crisis to the world, largely through social media.
The UK is to provide resettlement to "thousands" more Syrian refugees in response to the worsening humanitarian crisis, David Cameron has announced.
An image of a little boy wearing a bright red t-shirt and shorts lying face-down in the surf on a beach in one of Turkey's prime tourist resorts sweeps across social media.
Thousands of migrants are arriving in mainland Greece as the government prepares for talks on tackling the huge number of people reaching its shores.
A satellite image confirms that the main temple in the ancient city of Palmyra in northern Syria has been destroyed, the United Nations says.
Palmyra's ancient Temple of Bel is still standing despite an attempt by Islamic State (IS) militants to blow it up, Syria antiquities chief says.
The Islamic State (IS) militant group has destroyed part of another temple at the ancient Syrian site of Palmyra, activists and witnesses say.
