Twitter and other social media started circulating the Academy Award winner's death - falling 60-ft down 'Kauri Cliffs' - earlier this week.
Many posts included a link to an apparently legitimate news website that confirmed the 'breaking news'.
"Preliminary reports from New Zealand Police officials indicate that the actor fell more than 60-feet to his death on the Kauri Cliffs while on-set. Specific details are not yet available," the spoof article says.
However, the 'Global Associated News' website is a fake, set up specifically for circulating false stories.
Duvall has joined a growing list of celebrities falsely declared dead this month, including Bill Cosby, 'Science Guy' Bill Nye, and John Cena, who "died" while practising a move with The Rock.
