10.19.2006 -- Army Staff Sgt. Bryce Syverson spent 15 months in Iraq before he was diagnosed by military doctors with post-traumatic stress disorder (PTSD) and sent to the psychiatric unit at Walter Reed Medical Center, CBS News correspondent Sharyn Alfonsi reports. "It ended up they just took his weapon away from him and said he was non-deployable and couldn't have a weapon," says his father, Larry Syverson. "He was on suicide watch in a lockdown."

That was last August. This August, he was deployed to Ramadi, in the heart of the Sunni triangle - and he had a weapon. He's still there. Under pressure to maintain troop levels, military doctors tell CBS News it's become a "common practice" to recycle soldiers with mental disorders back into combat. "It's flat-out not a good idea," says Dr. John Wilson, an expert in combat trauma.

One study estimates that about 16 percent of soldiers returning from Iraq have PTSD. But military officials say they don't keep tabs on how many troops still fighting have been diagnosed. Most soldiers are never screened, a GAO report finds.

Wilson says the danger of having someone with PTSD at the front lines is that they are at risk themselves and put their units at risk and could break down under the stresses of combat. "Basically, it's like your worst day is every day. It gets worse every day," says Army Specialist Jason Gunn, a decorated soldier.

Gunn was critically injured in Baghdad when the Humvee he was driving hit an IED. His friend was killed in the explosion. "I blame myself," Gunn says. Gunn became depressed and paranoid. Doctors said he was sick, suffering from PTSD. But just four months after the deadly explosion, he was sent back to Iraq. "The Army sent us an e-mail saying they recognized Jason was suffering from PTSD, but was 'in his best interest' if he 'faced his fears' and went back to the front," says Pat Gunn, his mother.

Wilson says this does not make sense "at all."

"To put someone in that situation and say 'face your fears' is contrary to all current medical and scientific knowledge about PTSD," Wilson says. Jason Gunn says he thinks he was re-deployed so the military could keep up numbers in the ranks.