Officials say vials of powerful narcotics were drained with a syringe and replaced with water at Nassau University Medical Center's intensive care unit, and the discovery prompted a legal battle that has pit the hospital against its own employees.

Officials at the East Meadow hospital say 27 vials of fentanyl, phenobarbital, morphine and other drugs that were kept in a secure storage unit in the ICU had been tampered with. The discovery was made on July 23, and the following day the hospital ordered all staff members with access to the vials to undergo drug testing.

But the union representing nurses rejected the order, citing the employees' rights.

The union says it was told by NUMC that the Nassau County district attorney and the Federal Drug Administration told the hospital's acting CEO and medical director to disregard the union demands and instead test all employees who had access to the drugs. The Nassau DA's office says it is "not aware of any employee issuing that directive to the hospital."

Officials say 25 employees with access to the storage unit submitted urine tests, but the nurses' union sued to prevent the results of the tests from being released. The union argued that a collective bargaining agreement prevented administrators from randomly drug testing workers, and that there first needed to be probable cause that indicated substance use by employees.

A state Supreme Court justice on Monday approved a compromise in which the test results would be delivered to the judge with a list of the substances that were missing, instead of releasing the full drug test results to the hospital, in order to protect employee privacy.

News 12 asked the hospital whether any patients who needed the drugs were given water. The hospital said patient safety was not in danger.

NUMC said in a statement:

NUMC declined to comment further, citing the pending investigation.