CHARLESTON, W.Va. (AP) — A fourth lawsuit has been filed involving the sudden deaths of patients at a West Virginia veterans hospital where a former nursing assistant admitted giving them wrongful insulin injections.

A federal lawsuit was filed Wednesday in the death of Robert Lee Kozul Sr. at the Louis A. Johnson VA Medical Center in Clarksburg in January 2018. The 89-year-old Army veteran was from Fairmont.

Charleston attorney Tony O’Dell filed the lawsuit on behalf of Kozul’s son, James Forrest Kozul.

The lawsuit, which seeks unspecified damages, is the latest to allege a widespread system of failures at the hospital. The suit said many more unexplained deaths occurred by the time the medical director alerted the Department of Veterans Affairs' Office of Inspector General.

“Emergency department staff openly commented that if patients were admitted to Floor 3A they would die,” the lawsuit said.

Former hospital nursing assistant Reta Mays pleaded guilty last week to intentionally killing seven patients with fatal doses of insulin. Mays, 46, faces up to life in prison for each murder. No sentencing date has been set.

Mays admitted at a plea hearing to purposely killing the veterans, injecting them with unprescribed insulin while she worked overnight shifts at the hospital in northern West Virginia between 2017 and 2018. Her motive is still unclear. U.S. Attorney Bill Powell said authorities did not receive a “satisfactory response” to questions about the reasoning behind her actions.

The lawsuit said the federal government is legally liable for the medical negligence of the hospital staff, who ordered no testing to investigate the cause of Robert Kozul's unexplained severe hypoglycemia, or low blood sugar. He died the next day.

The lawsuit said Mays was not qualified to be a nursing assistant when she administered an insulin shot to Kozul, and her supervisors failed to stop her from performing the injections.

No autopsy was performed until Kozul's body was disinterred more than a year later at an Air Force base in Dover, Delaware, the suit said. A medical examiner declared his death was caused by the insulin injection.

Similar lawsuits have been filed in the April 2018 deaths at the hospital of Air Force veteran George Nelson Shaw Sr. and Army veteran Felix Kirk McDermott and the June 2018 death of Navy veteran John William Hallman.

The VA is the government’s second-largest department, responsible for 9 million military veterans. The agency’s former director was fired in 2018 in the wake of a bruising ethics scandal and a mounting rebellion within the agency, and the doctor who President Donald Trump nominated to replace him had to withdraw his nomination amid accusations of misconduct.