WASHINGTON — Frustrated by delays in health care, injured Iraq war veterans accused VA Secretary Jim Nicholson in a lawsuit of breaking the law by denying them disability pay and mental health treatment.

The lawsuit against the U.S. Department of Veterans Affairs, filed Monday in federal court in San Francisco, seeks broad changes in the agency as it struggles to meet growing demands from veterans returning home from Iraq and Afghanistan.

Suing on behalf of hundreds of thousands of veterans, it charges that the VA has failed warriors on numerous fronts. It contends the VA failed to provide prompt disability benefits, failed to add staff to reduce wait times for medical care and failed to boost services for post-traumatic stress disorder.

The lawsuit also accuses the VA of deliberately cheating some veterans by allegedly working with the Pentagon to misclassify PTSD claims as pre-existing personality disorders to avoid paying benefits. The VA and Pentagon have generally denied such charges.

"When one of our combat veterans walks into a VA hospital, then they must see a doctor that day," said Paul Sullivan, executive director of Veterans for Common Sense, which filed the lawsuit. "When a war veteran needs disability benefits because he or she can't work, then they must get a disability check in a few weeks."

"The VA has betrayed our veterans," Sullivan said.

VA spokesman Matt Smith said Monday he could not comment on a pending lawsuit.

"Through outreach efforts, the VA ensures returning Global War on Terror service members have access to the widely recognized quality health care they have earned, including services such as prosthetics or mental health care," Smith said. "VA has also given priority handling to their monetary disability benefit claims."

The lawsuit comes amid intense political and public scrutiny of the VA and Pentagon following reports of shoddy outpatient care of injured soldiers at Walter Reed Army Medical Center and elsewhere.

The complaint seeks to represent between 320,000 and 800,000 veterans of the Iraq war who lawyers say are at risk of having PTSD. Ultimately, a federal judge will have to decide whether the lawsuit is properly deemed a class action that adequately represents them.

As of March 31, roughly 52,375 Iraq veterans were evaluated at VA facilities for suspected PTSD, according to an internal quarterly VA report released Monday to The Associated Press.

"Unless systemic and drastic measures are instituted immediately, the costs to these veterans, their families and our nation will be incalculable, including broken families, a new generation of unemployed and homeless veterans, increases in drug abuse and alcoholism, and crushing burdens on the health care delivery system," the complaint says.