09/04/2014 04:17 EDT | Updated 09/05/2014 10:59 EDT

Joan Rivers Cause Of Death: Comedian Dies At 81 Following Cardiac Arrest, Induced Coma

Comedian Joan Rivers is dead at age 81, her daughter Melissa Rivers confirmed in a statement Thursday.

Update: The New York state medical examiner said Friday that Rivers' cause of death remained unclear following an autopsy and further tests are required, the Associated Press reported.

The state health department is investigating Joan Rivers' cause of death, according to the New York Times, following a procedure on her vocal cords that sent the the iconic comic and actress into cardiac arrest at a doctor's office on Aug. 28. Rivers was rushed to Mount Sinai hospital in New York City, according to TMZ, who broke the news.

Doctors at the hospital put Rivers into a medically-induced coma. On Tuesday, daughter Melissa said her mother remained on life support.

On Wednesday, Melissa Rivers indicated that her mother had been moved out of intensive care and into a private room. Rivers died the following day. TMZ reports Melissa took her mother off life support "so she could pass comfortably in a private room."

"It is with great sadness that I announce the death of my mother, Joan Rivers. She passed peacefully at 1:17pm surrounded by family and close friends. My son and I would like to thank the doctors, nurses, and staff of Mount Sinai Hospital for the amazing care they provided for my mother," Melissa Rivers said in a statement.

TMZ reported Thursday that Rivers' death had been reported to the New York medical examiner's office. The Yorkville Endoscopy clinic is under investigation, according to CNN.

Rivers was a tireless performer with a career that spanned six decades. She was working just days prior to her hospitalization, hosting an Emmys red carpet fashion review for the E! Network on Aug. 25.

This is a developing story...

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