The New York Police Department admitted on Saturday that they are investigating the death of legendary comedienne Joan Rivers.

A law enforcement source spoke with The Hollywood Reporter and confirmed that the NYPD had opened up an investigation after the Fashion Police host passed away earlier in the week.

"Yes, NYPD is investigating," the source admitted. "We investigate all such deaths, meaning 'not by natural causes.' Although it might end up being ruled natural by the [medical examiner], when it's not readily apparent, we investigate."

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As previously reported, the New York State Department of Health said they are investigating the Manhattan clinic where Rivers went to undergo throat surgery. During the operation, the 81-year-old stopped breathing and had to be rushed to the hospital.

After being placed in a medically induced coma ahead of last weekend, she passed away on Sept. 4, with her daughter Melissa Rivers confirming the sad news.

An autopsy was conducted on Rivers, but came back inconclusive as the medical examiner could not find a clear "cause and manner of death."

A more thorough examination of Rivers was planned, including toxicology reports and interviews with clinic staff.

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