The family of Diane Keaton has expressed gratitude for the messages of love and support received after the 79-year-old actor died of pneumonia last week.

The Academy Award-winning US actress had battled ill-health privately for months, with only her close family around her.

Thousands of fans posted messages to social media, praising Keaton's commitment to causes and her humanity, for which Keaton's family were grateful, they said in a statement to People magazine.

"The Keaton family are very grateful for the extraordinary messages of love and support they have received these past few days on behalf of their beloved Diane, who passed away from pneumonia on October 11," the statement read.

Keaton, who appeared in more than 60 films, including The Godfather trilogy, The First Wives Club a

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