A Syrian media activist group that reports on Islamic State group activities says that one of its journalists has been assassinated in Syria.

The group, which calls itself Raqqa is Being Slaughtered Silently, says Ahmad Mohamed al-Mousa was killed in the northern province of Idlib on Wednesday by unknown masked assailants.

The group, based in the northern city of Raqqa, reported al-Moussa's assassination through its Twitter account without providing more details.

Several members of RBSS have been killed in the past.

In October, a founding member of the group and another Syrian activist were found slain in in southern Turkey. The group blamed IS for the killings.

The New York-based Committee to Protect Journalists which honored the group last month with its 2015 International Press Freedom Award condemned al-Mousa's murder.