WASHINGTON, (Reuters) – U.S. prosecutors have charged a Canadian-born man with aiding Islamic State militants. He was accused of throwing grenades during battle and working alongside propagandists who promoted the execution of hostages such as James Foley.

Mohammed Khalifa was identified by the Department of Justice as being a leading figure in English-language media of Islamic State of Iraq and Syria (also known as ISIS).

According to the department, Khalifa was an English-language recruiter and a combatant before being captured by U.S.-backed Syrian Democratic Forces in 2019. This militia group controls large parts of Syria.

The Federal Bureau of Investigation recently had him arrested. On Saturday, the U.S. District Court in the Eastern District of Virginia dismissed the charges.

After releasing video footage in 2014 showing the murders of Foley and Steven Sotloff (U.S. journalists), and British aid workers Alan Henning, Islamic State became a global phenomenon. U.S. authorities allege that Khalifa was part of the group responsible for the publicizing the videos.

Khalifa could spend the rest of his life behind bars if convicted.