An Oregon hospital has been sued for $303 million after a hospital employee was accused of swapping patients’ medications for water, several news outlets reported.

The complaint, obtained by KDRV, was filed on Tuesday, September 3, by 18 former patients of Asante Rogue Regional Medical Center in Medford, Oregon, against the medical facility in Jackson County District Court.

In their complaint, the patients accuse the medical center of negligence due to “the actions of a hospital employee” who, among other things, failed to “adequately screen and monitor” his employees to “follow protocols” and failed to “properly warn and control the use of the unsafe tap water.”

The complaint comes after a former nurse at the hospital, Dani Marie Schofield, was arrested and charged with second-degree assault after she was accused of substituting tap water for patients’ fentanyl in IV bags, according to the Associated Press and Rogue Valley TimesAccording to the complaint, these measures led to “bacterial infections” in patients.

“Defendant Asante’s employee misused pain medications prescribed to plaintiff’s patients who were suffering from pain,” the lawsuit filed Tuesday states. The employee also “exposed” patients to “bacteria and non-sterile needles.”

“All plaintiffs have suffered pain that they say they would not have otherwise suffered and that they would not have had to endure over an extended period of time,” the lawsuit states.

The plaintiffs were notified by Asante Rogue Regional Medical Center in December that their IV bags containing fentanyl had been replaced with tap water, the complaint says, according to AP. Of the 18 plaintiffs who filed the complaint, nine are dead, according to the newspaper.

The lawsuit seeks $303 million in damages for medical expenses, lost income and the pain and suffering of the deceased, AP reported.

Asante Rogue Regional Medical Center and Shlesinger and deVilleneuve, the law firm representing the patients, did not immediately respond to PEOPLE’s request for comment.

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In February, a separate lawsuit was filed against the hospital and Schofield, alleging that Schofield replaced a 65-year-old patient’s fentanyl infusion with tap water, resulting in his death, the Rogue Valley Times.

Schofield was arrested following a Medford police investigation, according to the AP, which was launched after hospital officials reported a spike in cases of central venous catheter infections at the medical center between July 2022 and July 2023. She has pleaded not guilty.