US sergeant slaughtered Afghan victims with grenades and powerful machine guns and cut their fingers as trophies, then dropped weapons near their bodies to make them appear to have been combatants

A US army staff sergeant slaughtered Afghan victims with grenades and powerful machine guns during patrols in Kandahar province, then dropped weapons near their bodies to make them appear to have been combatants, an act that annul every human dignity and rights conventions.

Staff Sgt. Calvin Gibbs, of Billings, Montana described by a comrade as "evil incarnate" cut fingers off the corpses of three Afghan civilians.

His lawyer alleged that he had nothing to do with any plot to slaughter those unarmed men for sport. A court martial opened for the soldier who has pleaded not guilty to 16 criminal charges ranging from murder to taking the fingers as bloody mementos.

Of the five soldiers charged as part of the "kill team" within the platoon, three have pleaded guilty and agreed to testify against Gibbs, who faces up to life in prison without parole if convicted.

Gibbs, 26, is the highest-ranking of those charged. Others in the unit, including some of his co-defendants, portrayed him as an imposing sociopath with little respect for life - a man who gunned down dogs without provocation, threatened fellow soldiers and who tallied his kills with skull tattoos on his calves.

Another lead figure in the plot, Pvt. Jeremy Morlock, testified Monday that Gibbs played with the corpse of the first victim, a teenager, as if it was a puppet. The jurors were shown graphic photographs, including one in which Morlock stood over the victim's body and held up his head as though he had just bagged a deer.    

Gibbs, who had more combat experience than most of the others, did talk frequently of previous shootings he'd been involved in - including one in Iraq, when Gibbs fired on a car that refused to stop at a checkpoint, only to later learn that the vehicle was carrying an innocent Iraqi family.