Two veterans hanged themselves in the unit, The Dallas Morning News reported. The most recent occurred April 4, when a man used a bed sheet to hang himself from a door frame, while another man used a wheelchair and a door frame.

Two men took their lives in January after being discharged.

Dr. Catherine Orsak, head of mental health for the VA in North Texas, said the hospital has already spent $250,000 to replace door knobs, shower heads and other fixtures that could be used for suicide.

"That's what makes this even more shocking and painful," she said. "No one was ignoring this, and everyone was working hard on the fixes. And then you have a tragedy and you realize there's more you can do, and some patients have such a will to end their lives, it's hard to protect them."

Ten patients remain in one wing of the 51-bed unit. Orshak said the number of patient checks has been increased. Patients have been sent to other government hospitals and two private ones.