The U.S. Office of Special Counsel sent a letter to President Obama on Thursday blasting the Department of Veterans Affairs for its failure to discipline administrators who retaliated against whistleblowers in Phoenix, Ariz., reported The Arizona Republic.

Special Counsel Carolyn Lerner wrote in the letter that VA officials did nothing to protect whistleblowers who raised alarms about dangers and harmful incidents occurring in various VA facilities, and sometimes even tried to harm them, according to CNN.

Lerner focused on the case of a VA doctor, Katherine Mitchell, who blew the whistle on problems at Carl T. Hayden Medical Center in Phoenix.

Mitchell told officials that emergency room nurses were not properly trained and that patients were harmed because the nurses failed to conduct appropriate triage procedures. She identified at least 110 cases in which Emergency Department (ED) "patients were improperly triaged and experienced dangerous delays in care," including a patient with a history of strokes waiting nearly eight hours for treatment after showing signs of low blood pressure.

After Mitchell complained, VA officials investigated, transferred and harassed her, according to Lerner.

"I am concerned by the VA's decision to take no disciplinary action against responsible officials. The lack of accountability for the Hayden VAMC leaders sends the wrong message to veterans served by this facility, including those who received substandard emergency care," Lerner wrote. "The failure to take appropriate discipline, when presented with clear evidence of misconduct, can undermine accountability, impede progress, and discourage whistleblowers from coming forward."

The VA's Office of the Medical Inspector eventually substantiated Mitchell's allegations, finding that no nurses completed a nationally-recognized, comprehensive triage training regimen, and "only 11 of the 31 nurses had completed any triage training at all." That investigation was conducted after Mitchell had already been removed from her position as acting director of the ED, according to The Arizona Republic.

Lerner wrote that she had "sought additional information from the VA on its decision not to impose discipline on any responsible officials" but said no adequate justification was provided.

She also cited examples in several other VA offices in which officials failed to take appropriate disciplinary action, even when presented with clear evidence of misconduct.

"The lack of accountability in these cases stands in stark contrast to disciplinary actions taken against VA whistleblowers," Lerner said, noting that the VA has often attempted to fire or suspend whistleblowers for "minor indiscretions" or "for activity directly related to the employee's whistleblowing."

"While OSC has worked with VA headquarters to rescind the disciplinary actions in these cases, the severity of the initial punishments chills other employees from stepping forward to report concerns," Lerner wrote.