Joan Rivers' death was seemingly covered up, based on a private investigation that revealed new evidence.

Radar Online reported that they were able to obtain two official reports on Joan Rivers' death, which allege that government officials and medical experts covered up what really led to the comedienne's untimely passing.

World-renowned forensic pathologist Dr. Cyril Wecht said that he was stunned by the outright "negligence" of doctors from Yorkville Endoscopy. The said Upper East Side clinic is where Joan Rivers had her fateful throat operation that put her in a coma in August 2014.

The then 81-year-old comedy icon died a week later on Sept. 4, 2014.

"You have gross negligence here. ...This is a death that should not have occurred," he blasted.

Respected private investigator Danno Hanks also reviewed the new documents secured by the news site.

"It looks like a cover-up!" exclaimed the DEA and FBI consultant.

"Over and over again, I'm looking at pages filled with stone-walling by the doctors, the center and its staff, missing data logs, suspicious IT personnel and more."

"It's breathtaking," he pointed out, referring to the apparent cover-up surrounding Joan Rivers' death.

Glaring irregularities were detailed in the new evidence. One was how Joan Rivers did not undergo an autopsy when she was disconnected from life support at New York's Mount Sinai Hospital.

Celebrity ear, nose and throat doctor Gwen Korovin was also never listed in the medical record, eventhough she reportedly performed two unsanctioned procedures on the late TV personality.

Dr. Lawrence Cohen, who heads Yorkville Endoscopy, also allegedly lied about several details that took place during the procedure.

Entertainment Tonight previously reported about how Melissa Rivers lashed out at Yorkville Endoscopy for not taking care of her mother.

"[Melissa Rivers] is outraged by the misconduct and mismanagement now shown to have occurred before, during and after the procedure," said her lawyers.