LOS ANGELES — Authorities are investigating the death of Kim Porter, the former girlfriend of Sean "Diddy" Combs and the mother of three of his children, authorities said Thursday.

Porter, who was born in Columbus, Georgia, and would have turned 48 next month, was found unresponsive Thursday morning in her home in the Los Angeles neighborhood of Toluca Lake, the Los Angeles County medical examiner's office said.

No cause of death had been determined pending an autopsy, the medical examiner's office said.

Combs, 49, the multiple Grammy-winning rapper and producer, and Porter, a model, singer and actress who was a member of the groups 3 Brown Girls and Girl 6, were a couple on and off from 1994 until 2007. They had three children — a 20-year-old son and twin 11-year-old daughters.

Porter and Combs also raised Porter's 27-year-old son from her relationship with the singer Albert Brown, the new jack swing singer and producer better known as Al B. Sure.

When the couple split up in 2007, Porter said she and Combs "will remain friends and committed parents to our children."

Porter's death stunned many in the music industry and others who knew her and Combs. The singer Missy Elliott said on Twitter that her "heart aches so much for her four children."

My heart just aches so much 4 her children????She Loved them dearly she was proud of her kids & they Loved their mother so much?? & Prayers for @Diddy during such a difficult time?????? #KimPorter those that know you will always remember your SMILE your LAUGH

& KIND HEART???? pic.twitter.com/3FjrzWuBjr — Missy Elliott (@MissyElliott) November 16, 2018

The rapper 50 Cent expressed his condolences, calling Combs and Porter "soul mate types."

"I know Puff is hit right now, he loved her for real," 50 Cent wrote, adding: "Chin up puff, Positive vibes only."

Dwyane Wade, the National Basketball Association star, tweeted: "In my brief interaction with Kim Porter she was nothing but a bright light. My family and i prayers goes up for her 2 twin daughters and her two sons."

My heart is hurting for @Diddy and his family. In my brief interaction with Kim Porter she was nothing but a bright light. My family and i prayers goes up for her 2 twin daughters and her two sons. #RestInHeaven — DWade (@DwyaneWade) November 16, 2018