WASHINGTON -- Before a crowd of grieving family members in Pittsburgh, Veterans Affairs officials defended their patient safety and executive bonus programs Monday, dismissing assertions that the department doesn't hold poor managers accountable for failure.

"VA has a long-established record of providing safe health care," said Robert Petzel, under secretary for health at the Department of Veterans Affairs. "The patient care issues the Committee has raised are serious, but not systemic."

However, lawmakers and family of injured veterans at the outside-the-beltway hearing questioned whether that is true.

Monday's hearing included a detailed look at "preventable deaths" at six different VA health care facilities, including at least five deaths from Legionnaires' disease at the VA Pittsburgh Health Care system.

Witnesses tearfully recounted family members' deaths due unsanitary practices, surgical mistakes and poor supervision of VA employees.

They also bristled at reports that numerous executives from those facilities later received bonuses -- some totaling tens of thousands of dollars -- for meeting performance metrics.

Members of the House Veterans Affairs Committee and a recent Government Accountability Office report have labeled the bonus system as broken, and lawmakers are pushing to ban all VA executive bonuses for five years.

Petzel called the patient deaths tragic and upsetting, and said department officials are conducting appropriate administrative and criminal investigations.

But he also insisted that the cases are all isolated incidents reflective of a massive health care system, not a incompetent or uncaring bureaucracy.

"While no health care system can be made entirely free from inherent risks, when adverse incidents do occur, VA studies them to fully understand what has happened," he said.

Petzel said "substantial disciplinary actions" have already taken place in Pittsburgh, Atlanta and several other regional VA systems. The department is also reviewing its bonus award procedures.

Lawmakers said they expect more.

"We will simply not tolerate substandard care for our veterans under any circumstance," said committee chairman Rep. Jeff Miller, R-Fla. "When we hear about it, we will investigate it."