BALTIMORE (AP) — A Johns Hopkins Hospital gynecologist accused of secretly videotaping patients wore a pen around his neck that may have been used to conceal a camera, according to the employee who reported the doctor.

The employee told hospital officials of her suspicions Feb. 4, according to a letter from the hospital’s CEO, Dr. Paul B. Rothman. The letter was dated Tuesday and sent to the law firm of Silverman Thompson Slutkin & White, which is working with the Maryland Crime Victims’ Resource Center. The law firm gave a copy of the letter to The Associated Press on Wednesday.

The employee’s report to officials ultimately led to the discovery that Dr. Nikita Levy had been recording patients during exams at a Hopkins clinic. Police have said Levy, 54, killed himself in his home on Feb. 18.

Rothman’s letter said the Hopkins employee had noticed what she believed to be a device, like a writing pen, that Levy had worn around his neck while examining patients. She said she believed the device was a camera.

Rothman writes that Hopkins security personnel questioned Levy at his office on Feb. 5, and devices similar to the one described by the employee were seen in the office and on Levy.

Levy was barred from patient contact that day and escorted off hospital grounds. Hopkins notified Baltimore police the day after, and investigators have said they found large amounts of multimedia evidence.

Police have said more than 2,000 patients and former patients of Levy have called a hotline set up by the hospital. Class-action lawsuits have been filed against Hopkins.

Meanwhile, investigators are trying to determine if anyone else was involved in making the records, and whether any have been posted on the Internet or sold.

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