Dr. Lawrence Cohen, the medical director of Yorkville Endoscopy, where Joan Rivers went into cardiac arrest last month, has stepped down after being asked to leave, ABC News reports. The 81-year-old comedian passed away on Sept. 4, a week after being hospitalized following an unplanned throat biopsy during a routine endoscopy at the Manhattan clinic.

The clinic previously refuted a report from the New York Daily News, claiming it had never administered general anesthesia or conducted a vocal-cord biopsy on patients at its facility. "A biopsy of the vocal cords has never been performed at Yorkville Endoscopy," the clinic reportedly said in a statement. "General anesthesia has never been administered.

"Our anesthesiologists monitor the patient continuously utilizing state-of-the-art monitoring equipment, and remain at the bedside throughout the procedure and into recovery," it said.

BREAKING: Medical director of Yorkville Endoscopy where #JoanRivers went to cardiac arrest is out

— Eyewitness News (@ABC7NY) September 12, 2014

Rivers had gone in for a procedure that friends called “a diagnostic procedure [to] see why her voice had gotten raspy,” the Daily News reported. When the doctor performing the endoscopy found “something” on her vocal cords, another doctor, whom she brought along with her, asked “if he could use their instruments,” to perform a throat biopsy, the report stated. It was reportedly a “huge no-no” for Yorkville Endoscopy to allow an outside doctor to come in and perform an operation without any fore mention. During the biopsy, Rivers went into cardiac respiratory arrest and was rushed to Mount Sinai. She passed away a week later. 

CORRECTION: An earlier version of this story mistakenly referred to Dr. Lawrence Cohen as Dr. Michael Cohen in the main headline.