United Kingdom, July 28 -- Kris Jenner's mother Mary Jo's cause of death has been revealed.

The family matriarch passed away on July 16, aged 91, with her death certificate listing acute cardiopulmonary arrest as the immediate cause of her death.

The certificate, obtained by Us Weekly, also listed acute respiratory failure and metastatic lung cancer as contributing factors.

According to the documentation, Mary Jo - known affectionately by friends and family as MJ - was cremated on July 23, with no autopsy performed.

Kris announced her mother's death in a post on Instagram on July 16, as she wrote: "Today, we said goodbye to my beautiful Mommy MJ.

"There are no words that could ever capture what she has meant to me or the heartbreak o...