Embattled veterans chief Shinseki fights on
Veterans Affairs Secretary Eric Shinseki has called the delays to veterans' medical care "reprehensible" as calls mount for him to resign.
Writing in USA Today, he vowed to address the problems outlined in Wednesday's damning watchdog report.
It found that 1,700 veterans in Phoenix were left to fend for themselves, not even on doctors' waiting lists.
Republican Arizona Senator John McCain is leading calls for him to step down, echoed by some Democrats.
But House Speaker John Boehner said on Thursday that he's reserving judgement about the embattled secretary.
The report by the inspector general for the Department of Veterans Affairs (VA) found systemic problems at the VA nationwide, but particular problems in Phoenix.
It said about 1,700 veterans in need of care there were "at risk of being lost or forgotten" after being kept off the official waiting list.
The average wait at that hospital for a first appointment was 115 days, 91 days longer than the hospital reported.
Mr Shinseki wrote that the findings of the report were "reprehensible to me and to this department, and we are not waiting to set things straight".
He had ordered a nationwide audit of care, he said, and taken action to put the leadership team in Phoenix on administrative leave pending an investigation.
"After 38 years in the Army, I am honoured and privileged to serve veterans as the secretary of Veterans Affairs, and I remain committed to providing the high-quality care and benefits that veterans have earned and deserve. And we will."
White House press secretary Jay Carney said President Obama had been briefed on the findings and found them "extremely troubling."
Justin Youse, 33, a former Army sergeant, was taking fire with his unit in Nasiriyah, Iraq, in July 2003.
"I jumped out of a truck. I'd jumped out of helicopters before, but this time I landed in a ditch and ended up paralysed," Mr Youse says.
He was medevaced (medical evacuation) to Germany and applied for disability. The military designated his case as being 10% disabled, which meant he was deemed fit enough to work.
"The VA said they had records showing I had been medevaced out of Iraq. But they said they didn't have proof I was there. By then I also had PTSD [post-traumatic stress disorder]."
Mr Youse said he was paralysed from his back injury and after five surgeries has been able to move with the help of a wheelchair, a walker and then a cane. He is still going through surgeries.
"Last year I was granted 100%. I was told the delay was because the VA has a backlog. Personally I felt it was like veterans are guilty until we prove ourselves innocent. We don't have injuries until we prove wehave them."
The president has vowed that any evidence of misconduct would be dealt with.
The US veterans health system serves about nine million former US military service members.
It is a series of hospitals and other medical facilities separate from the US military health system.
Eligible veterans apply for the care, which is often free or low-cost.