Rip Joan Rivers -- who made the world laugh for over 50 years with her jokes, put-downs and one-liners has died in NYC ... a week after her heart suddenly stopped beating during vocal cord surgery.
She was 81.
Joan's daughter Melissa Rivers took her mom off life support so she could pass comfortably in a private room.
The death has been reported to the NYC Medical Examiner's Office -- and officials tell TMZ the office will open an investigation to determine cause of death.
Melissa just issued a statement saying, "It is with great sadness that I announce the death of my mother, Joan Rivers." "She passed peacefully at 1:17 PM 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."
"Cooper and I have found ourselves humbled by the outpouring of love, support and prayers we have received from around the world.They have been heard and appreciated."
"My mother's greatest joy in life was to make people laugh. Although that is difficult to do right now, I know her final wish would be that we return to laughing soon." Rivers is widely credited for opening doors for countless female comediennes. She broke through in a big way during her appearances on "The Tonight Show" with Johnny Carson. She also famously enraged Carson by accepting a gig to host a competing late night show on FOX. Carson never spoke to her again.