BEVERLY — The alleged theft of nearly 18,000 pills from Beverly Hospital, Addison Gilbert Hospital, and two satellite locations, could be among the largest instances of drug diversion from a hospital in the country, based on accounts of similar drug thefts. 

Lisa R. Tillman, 49, of Salem, was arraigned last week in Salem District Court on a charge of larceny of a controlled substance and is currently free on $10,000 personal surety while she awaits trial. 

Tillman has pleaded not guilty, but allegedly told police that she was taking the pills for personal use during a difficult time in her life, flushing the ones she did not consume. She has denied selling or distributing the pills to anyone else. 

Most of the pills were various forms of opiates, including Percocet, Vicodin, and OxyContin. 

Tillman, a pharmacy technician who worked overnights, allegedly stole the drugs by altering computer records to mark them as outdated, then removed them from automated dispensing machines at Beverly Hospital, a satellite location in Danvers, and at Addison Gilbert Hospital in Gloucester and Bayridge Hospital, a Lynn psychiatric facility. 

A Department of Public Health investigator called the amount "astonishing" in her report, which was included in the court complaint. 

That report also indicated that the hospital's director of pharmacy said she was not familiar with requirements that two employees sign off when drugs are removed from a dispensing machine for disposal. 

A DPH spokeswoman confirmed this week that an investigation into Beverly Hospital remains ongoing and will remain open while the case against Tillman is pending. 

Asked whether others are facing disciplinary action as a result of the thefts and a failure to follow regulations requiring two people to sign off on all drug disposals, DPH spokeswoman Ann Scales said that information is part of the ongoing investigation and will be available after it is completed.

A hospital spokesman said last week that it is cooperating with all ongoing investigations into the incident. 

Besides the Department of Public Health, the Drug Enforcement Administration has authority over large-scale hospital drug diversions. 

Hospitals have been penalized over employee thefts and diversions in several high-profile cases. 

In 2015, Massachusetts General Hospital paid a $2.3 settlement to the U.S. Attorney's office to resolve allegations that lax controls over medication led to the theft of more than 16,000 pills by two nurses, and smaller thefts by a number of other employees, over a several-year period. 

As in the Beverly Hospital case, most of the pills that were stolen involved opiates. 

At the time, it was the largest settlement involving drug diversion at a hospital. 

Then, last August, the University of Michigan paid a $4.3 million settlement following a five-year investigation into violations of the Controlled Substance Act within its hospitals.

The investigation began after two employees suffered overdoses, one of them fatal, and the hospital system later admitted that at least 16,000 opiate pills disappeared from the system's 15 locations in a one-year period. 

The Salem News has filed a public records request for other drug diversion incidents in Massachusetts hospitals during the past decade.  

Courts reporter Julie Manganis can be reached at 978-338-2521, by email at jmanganis@salemnews.com or on Twitter at @SNJulieManganis.