Islamic State militants have killed at least 13 journalists and other media workers in Mosul since seizing the Iraqi city in 2014, a watchdog says, according to BBC News.

Reporters Without Borders (RSF) said they were among the jihadist group's "priority targets".

The fate of least 10 of the 48 media workers who have been abducted there over the past 16 months is unknown.

RSF said IS had also taken control of local TV and radio stations, turning Mosul into an "information black hole".

Their studios and equipment were also seen as "spoils of war" and had been used to pursue "information offensives", according to the RSF's Middle East and Maghreb chief, Alexandra El Khazen.

Equipment seized from Sama Mosul TV is believed to have been used to record the sermon delivered by the group's leader and self-proclaimed "caliph", Abu Bakr al-Baghdadi, at the city's Great Mosque in July 2014 - his first public appearance.