Saudi authorities on Friday killed six men who shot dead their relative, a Saudi soldier, in a video they posted online after they pledged allegiance to the leader of Islamic State.
Saudi state news agency SPA cited a statement by the Interior Ministry as saying security forces killed the men after they refused to surrender and exchanged fire with the police.
The video posted last month showed the shooting of a man identified as Badr Hamdi al-Rashidi, a member of Saudi Arabia's Special Emergency Force in the Qassim region, by men who pledged allegiance to Islamic State leader Abu Bakr al-Baghdadi.
It was not immediately clear if they acted on orders by Islamic State or on their own.
Islamic State has claimed responsibility for a series of bombings and shootings in Saudi Arabia since November 2014 that have killed more than 50 people, most of them Shi'ites but also more than 15 members of the security forces.
Saudi security officials say the group's supporters inside Saudi Arabia mainly act independently, depending on Islamic State for only limited logistical help and advice, making them harder to detect, but also less capable of attacks on well protected targets.
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