A nurse at an Oregon hospital allegedly replaced fentanyl with nonsterile tap water, introducing bacteria into a patient’s bloodstream that led to his death, a lawsuit filed this week alleges.

The suit accuses Asante Rogue Regional Medical Center and the nurse in question of negligence in the death of 65-year-old Horace Wilson. The attorney who filed the case said he’s investigating more potential claims, and two other lawyers said they have also heard from people who are worried they or their loved ones were affected.