Sgt. John Russell, a 44-year-old Texan, has been in the military 20 years. Russell was on his third tour of duty in Iraq and, as CBS News correspondent Bob Orr reports, there were signs he was in trouble.
His commanders feared Russell was on the edge. So, they took away his weapon and ordered him to counseling at a combat stress clinic in Baghdad.
And it was there Monday, officials say, that Russell opened fire, killing five fellow service members. Among his victims: Navy Commander Charles Springle, a licensed clinical social worker.
Today at their home in Sherman, Tex., Russell's 20-year-old son struggled to understand how his dad, a decorated electronics expert, now faces five counts of murder.
"He's got medals. He was doing good for the country," John Russell II said. "For him to do something like that, he couldn't of been in his right state of mind. They had to have put him to a breaking point. Because he just had to have lost it lost all train of thought to do anything like that."
Sgt. Russell's father said he may have snapped out of fear that his military career could be ended by a stress diagnosis.
"His life was over as far as he was concerned. He was gonna lose everything. I guess it was just too much," Wilburn Russell said.
Military investigators don't know what triggered the shootings, but say Russell was agitated when he was asked to leave the clinic after arguing with a counselor.
A short time later, Russell returned to the stress center with a weapon he apparently stole from his armed escort. The rampage played out quickly.
"His chain of command had concerns about him. He had been undergoing counseling within the command. Again, they had already taken the immediate measure of removing his weapon," Gen. David Perkins said.
The incident is the deadliest involving soldier on soldier violence in the six-year Iraq war. In response, the Army has launched an investigation to determine if it needs more people and facilities in war zones to deal with combat stress and soldiers on the brink.
"These are the canaries in the mine," said Patrick Campbell of Iraq and Afghanistan Veterans Of America. "If we don't start addressing these issues people are get more and more injured and it's going to get harder to treat them."
For Russell, who'd planned to be home by July, it's too late.
"We are crestfallen, heartbroken," Wilburn Russell said. "His mother is hiding in there crying. We're sorry for the families involved too."
Russell's family says they knew of no warning signs. Russell recently e-mailed his son on his birthday and just Sunday, e-mailed his mother for mother's day.