(CNN) -- Five Royal Marines have been charged with murder for the death of a man in Afghanistan's Helmand province last year, authorities said Sunday.
In all, authorities arrested nine Marines in connection with the death, but four were later released without charge, the British defense ministry said.
The men were part of Operation Herrick 14, as Britain's efforts in Afghanistan are known. Their case will now proceed through a military court system that mirrors the civilian legal system.
In its announcements of the arrests, and later the charges, the ministry offered little detail about the incident except to say it took place last year and described the dead man as "an insurgent."
However, the British newspaper The Independent said Saturday the Marines were arrested after police found footage on a laptop during a separate investigation into pornographic material.
The newspaper said the footage showed the Marines discussing whether they should offer medical aid to an injured man.
The man was wounded while trying to ambush a patrol. He later died -- although the death was not captured on the footage, the paper said.
By Sunday, a Facebook page supporting the men had gathered more than 36,000 followers.
"This page is set up to show support for the seven Royal Marine Commandos arrested for murder for an event which happened in Afghanistan 2011 where no civilians were injured and one gunman was killed who shot at them FIRST," the page said.