The official cause of Leachman's death was released on Thursday.
Leachman died on Wednesday at the age of 94.
The actress' rep confirmed to ET that Leachman died in her sleep of natural causes at her Encinitas, California, home on Wednesday.
Cloris Leachman has died at 94. A rep for the prolific actress confirmed to ET that Cloris died in her sleep Tuesday night.
In the wake of the celebrated actress' death, some of her famous friends and fans paid tribute to her legacy.
The Oscar-winning actress died in her sleep this week.