LONDON - A British Royal Marine convicted of murdering a wounded Taliban insurgent was sentenced Friday to a minimum of 10 years in prison.
A military judge told Sgt. Alexander Blackman he had "betrayed your corps and all British service personnel who have served in Afghanistan."
Two other marines were acquitted of the September 2011 killing in Afghanistan's southern Helmand province. They were charged after military authorities found footage of the incident on a helmet camera belonging to one of the men.
Blackman was recorded shooting the Afghan, who had been seriously wounded in an Apache helicopter strike, in the chest at close range with a pistol before quoting a phrase from Shakespeare - "Shuffle off this mortal coil."
He added: "Obviously this doesn't go anywhere, fellas. I just broke the Geneva Convention."
The three marines were tried anonymously, but a judge ruled Thursday that Blackman could be identified.
He is the first British service member convicted of murder since deployments to Afghanistan began in 2001.
British troops operate under rules of engagement, largely derived from the Geneva Convention, that dictate under what circumstances they are allowed to open fire.
Experts say the military has been strict about enforcing the rules after a disastrous period in Iraq, where there were multiple allegations of torture and abuse by British troops.
The murder in Helmand came five months into a six-month deployment during which Blackman's brigade had seen seven troops killed and several dozen wounded.
During his trial, Blackman said he had fired his gun out of a "lack of self-control, momentary lapse in my judgment" - but claimed he thought the insurgent was already dead.
Judge Advocate General Jeff Blackett told Blackman that "you treated that Afghan man with contempt and murdered him in cold blood.
"In one moment you undermined much of the good work done day in day out by British forces and potentially increased the risk of revenge attacks against your fellow service personnel."
Blackman was sentenced to life with no possibility of parole for 10 years, and dismissed with disgrace from the armed forces.