Moshe Markowitz, of Allentown, met the girl — a student at Warren Hills Regional High School — on chat site Omegle, but continued the conversation with her on Discord last January, Warren County Prosecutor James L. Pfeiffer said.
The alleged incident was reported by the victim's friend, authorities said.
Using the alias "Steven Jones," Markowitz engaged in sexually explicit conversations with the girl, Pfeiffer said.
A search of his Main Street home in Allentown turned up devices on which "graphic, sexually charged" conversations were found, Pfieffer said.
Online records show Markowitz is a physician for Lehigh Valley Physicians Group Pediatrics, and according to authorities, employed by the Lehigh Valley Health Network.
The doctor was charged in Warren County with third-degree child endangerment.
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