Raed al Fares gained prominence early in the uprising against Syrian regime leader Bashar al Assad with protest banners that drew international attention on social media.
Armed men in Syria's rebel and opposition-held Idlib province assassinated on Friday an activist who ran a radio station that provided independent news and satirised both Syrian regime leader Bashar al Assad and opposition groups, a war monitor reported.
The unidentified gunmen shot Raed al Fares, along with his friend Hamoud al Juneid, in the town of Kafranbel, home to the Radio Fresh station, the British-based Syrian Observatory for Human Rights said.
Fares gained prominence early in the uprising against the Assad regime, which began with mass demonstrations in 2011 and slid into civil war, with protest banners that drew international attention on social media.
The banners targeted Assad, his ally Iran, Western countries that Fares portrayed as selling out ordinary Syrians through their response to the crisis, and the militants who had emerged in the chaos.
Fares also distributed photographs and video clips showing the toll that war was taking in Kafranbel, providing a picture of life in parts of Syria where it was dangerous for foreign media to visit.
In 2014 Daesh gunmen shot him in the chest, but he survived.
By his own account, his offices were targeted both by regime bombardment and by militants, who abducted and tortured him several times.
In an opinion piece in June in the Washington Post, calling for the US to resume financial support for Radio Fresh, Fares wrote that "the terrorist groups (and the regime) see us as a direct threat."
The Tahrir al Sham alliance is the most powerful of several groups present in Idlib province. A Russian-Turkish deal to prevent further fighting in northwest Syria, the last rebel and opposition stronghold, has for now averted a planned regime offensive.
The Observatory has reported a succession of assassinations in Idlib over the past year targeting leaders from the area's major factions and political dissidents who publicly disagree with their governance.