An American Army sergeant shot and killed five fellow soldiers following an altercation at a military counseling center in Iraq on May 11, U.S. officials said.

Maj. Gen. David Perkins said May 12 that Sgt. John M. Russell of the 54th Engineering Battalion, based in Bamberg, Germany, has been charged with five counts of murder and one count of aggravated assault in the shootings.

Perkins said the dead included two doctors — one from the Navy and the other from the Army. The other three dead were enlisted personnel.The names of the victims were not released.

Attacks on fellow soldiers, known as fraggings, occurred during the Vietnam War but are believed to be rare in Iraq and Afghanistan.

A brief U.S. military statement said Russell was taken into custody following the 2 p.m. shooting at Camp Liberty, a sprawling U.S. base on the western edge of Baghdad.

Soldiers routinely carry weapons on bases, but the weapons are supposed to be unloaded.