Drake, Rihanna, and others mourn Kim Porter's demise

Singers Rihanna, Drake, Nicki Minaj, and others Hollywood stars mourned the death of Kim Porter, ex-girlfriend of rapper Sean "Diddy" Combs, who passed away on Thursday.

While the cause of death remains unclear, Porter, who shares three children with the rapper, was reportedly suffering from pneumonia for weeks. An autopsy is likely to be conducted to confirm the cause of death.

According to TMZ, authorities were called to the 47-year-old's residence in Los Angeles on Thursday after a 911 call reported "a patient in cardiac arrest."

Taking to his Instagram, Canadian rapper Drake uploaded a picture which shows Porter attending one of his concerts. He captioned the image as, "Sending peace and prayers to my brothers and to the big homie Puff. Love y'all and I am so sorry."

Nicki Minaj also reacted to Porter's death, and wrote, "The most heartbreaking news. My condolences to your children, family & friends. Sending love to Puff as well, I can't even imagine what you must be going through. Gone way too soon. Rest in Peace, Queen."

Rihanna also shared a heartfelt tribute to Porter, posting a series of photos of her with her children.

"This is heavy," Rihanna, 30, wrote. "Heartbroken about this man. We lost a real one today, beautiful inside and out. So many will be affected by this, some won't even know why. but the whole world was graced by the vibrance in your spirit. My deepest condolences to the ones that were blessed enough to know, meet, and love her! Such a special soul man! This doesn't even feel real! May God comfort and protect her children and loved ones! RIP."

Actress Viola Davis also sent her well wishes to Porter's family. "RIP Kim Porter! My heart breaks for your beautiful children and family," the Oscar winner wrote on Instagram.

"You are the true definition of being beautiful from the inside out," Lala Anthony wrote alongside a photo of Porter. "I'm praying hard for your family and all of our friends. heartbroken. GOD BLESS YOU. Rest easy."

Usher, 50 Cent, Ludacris, Teyana Taylor, Gabrielle Union and 'Real Housewives of Atlanta' star NeNe Leakes also expressed their sympathy.

Porter and Diddy, who began dating in the mid-1990s, called it quits in 2007. They had three children - Jessie James, D'Lila, and Christian - together.

The 47-year-old also had a son, Quincy, from her relationship with R&B artist Al B. Sure

.