BAGHDAD - A U.S. soldier suspected of shooting dead five fellow servicemen at a military clinic in Baghdad was charged with five counts of murder on Tuesday, the U.S. military said.

The military said Sergeant John Russell of the 54th Engineer Battalion, based in Bamberg, Germany, was suspected of being the man who went on a shooting spree on Monday at Camp Liberty, near Baghdad airport, in an incident that the top U.S. military officer suggested may have been triggered by stress.

U.S. President Barack Obama said he was shocked and deeply saddened by the horrible tragedy in which Russell is accused of walking into a counseling center for soldiers who are experiencing combat stress and opening fire, killing the five.

The suspect ... Sgt John Russell is charged with five specifications of murder and one specification of aggravated assault, the military said in a statement, adding that he is in military police custody.

Russell is from Sherman, Texas.

There were a total of five service members killed yesterday. Two were 55th Medical Company staff officers at the Liberty Combat Stress Control Center, it added.

The other three were Army enlisted soldiers who happened to be at the center at the time, it added.

The Pentagon identified one of those killed as Navy Commander Charles Springle, 52, of Wilmington, North Carolina, saying he died of injuries sustained in a non-combat related incident.

Admiral Mike Mullen, chairman of the U.S. military's Joint Chiefs of Staff said on Monday that the incident highlighted the need to redouble efforts to deal effectively with combat stress and of the risk of multiple deployments of soldiers.

An additional investigation ... is being conducted into the overall behavioral health services policies and procedures offered in Iraq, the statement said.

This suspected individual was apprehended outside of the clinic shortly after the shots were heard, said Major-General David Perkins, the spokesman for U.S. forces in Iraq, adding that his commander had earlier determined that it was best he have his weapon taken away.

It will include an examination of how the incident occurred. We will also examine the steps taken to see if we can reduce the possibility of another event like it occurring in the future, he said.