PARIS — French authorities revealed Tuesday that three Syrian nationals, all former or current advisers of Syrian President Bashar al-Assad, were charged on March 29 with complicity in crimes against humanity and war crimes.

The three former advisers are head of the National Security Bureau of the Ba'ath Party Ali Mamlouk, former head of the Syrian air force intelligence directorate Jamil Hassan, and air force intelligence officer Abdel Salam Mahmoud. It is the first time that such senior Syrian officials will stand trial in France for these sorts of crimes.

The French prosecution argues that these three Syrians were implicated in the disappearance and deaths of a French high school counselor in Damascus, Mazen Dabbagh, and his son Patrick who studied literature at Damascus University. The father and son, both dual Syrian-French nationals, were arrested in November 2013. Detained at one of the airports near the Syrian capital, they were interrogated and tortured by intelligence agents from the Syrian air force, believed to be one of the most powerful bodies in the regime.

A preliminary investigation into possible forced disappearances of the Dabbaghs was launched in 2015 after their family filed a complaint in France. A full probe was launched by French authorities in 2016, leading to the issuing of international arrest warrants two years later. With no news on their whereabouts, French authorities declared both of them dead in 2018. It is believed that Patrick was killed in 2014 and Mazen in 2017. Testimonies collected by French investigators suggest that among other forms of torture, the father and son were beaten with iron bars on the soles of their feet, subjected to electric shocks and had their fingernails torn out.