A prominent emergency room doctor who wrote a book on how to improve patient-physician relations faces charges he drugged and sexually assaulted one female patient and fondled another at a Manhattan hospital.

David Newman was to be released from jail on Wednesday after making bail. There was no immediate response to a request for comment from his attorney.

Authorities began investigating the 45-year-old Newman after a woman called police to report that she was sexually abused during a visit to Mount Sinai hospital emergency room on Jan. 12 to seek help for shoulder pain. She claimed that after nurses gave her a dose of morphine, the doctor entered her private room and told her he needed to give her a second dose.

As she fought to stay conscious, he masturbated, according to a criminal complaint. Amid news reports about the investigation, the second accuser came forward on Saturday to report that Newman had groped her breasts during a hospital visit last September, authorities said.

In a statement, Mount Sinai said it had suspended Newman, adding that he had not treated any patients since the investigation began.

"We take the nature of these allegations very seriously and continue to conduct our own extensive internal inquiry," the hospital said. "The health and safety of our patients are our primary concern."

In a recent op-ed piece advocating stricter gun control, Newman described himself as "an emergency room physician, an Army veteran who was deployed to a combat support hospital in Baghdad in 2005, and a biomedical researcher in the field of cardiac-arrest resuscitation."

Newman is the author of "Hippocrates' Shadow: Secrets From the House of Medicine," a book examining what it calls "the fraying of patient-doctor relations" and advocating a "new paradigm to rebuild the bridge between physicians and their patients."

Newman was ordered to return to court on Feb. 23.