QUEENS (WABC) -- A doctor in Queens is accused of raping three women in his apartment and also abusing three women at a hospital.
Dr. Zhi Alan Cheng worked at New York Presbyterian Queens Hospital, and prosecutors say there are other victims they are now trying to find.
Prosecutors say Cheng drugged and sexually assaulted his patients and others over a period of years, and they know that because he recorded it himself.
The investigation began last year when a woman accused Cheng of rape. Investigators then searched his phone and found evidence of many more victims.
"It's always difficult when you find anyone is a victim. It is always difficult to find out after the fact. You know, some might have known, some might have had a feeling, some had no Idea. I can't really talk in details about each of the victims, but I will tell you that it has been a traumatic type of case all around," said Queens DA Melinda Katz.
Some of the alleged assaults happened at the hospital, but videos show some at the doctor's home. Prosecutors say that while they have identified some of the victims, at least six other victims on the hard drive have not yet been identified. Because the victims were drugged, most did not know they were assaulted.
Attorney Nicholas Liakis represents a 19-year-old woman, who prosecutors say was drugged through her IV and raped by her New York Presbyterian Gastroenterologist, Dr. Cheng - who allegedly shot the assault on his phone.
"Having to go to the District Attorney's office and see a video of yourself unconscious, getting assaulted, after being drugged is..you know, that's unimaginable to deal with, so she's taking it day by day," said Liakis.
New York Presbyterian fired Cheng on the spot when he was first arrested. On Monday, the hospital described its responsibility to its patients as a sacred trust.
"As caregivers, we are responsible for the safety and well-being of our patients - it is a sacred trust. The crimes committed by this individual are heinous, despicable and a fundamental betrayal of our mission and our patients."
New York Presbyterian says they are fully cooperating with the Queens District Attorney's Office, the NYPD and the New York State Department of Health.
Cheng has been charged in connection with only six victims, but investigators are hoping more people who suspect they may be a victim to come forward.
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