Author Sir Terry Pratchett has died at the age of 66, his publishers have confirmed.

Best known for his Discworld series of novels, he had been suffering from Alzheimer's for the past eight years.

News of Pratchett's passing was shared on the author's Twitter page: 

Terry took Death’s arm and followed him through the doors and on to the black desert under the endless night.

— Terry Pratchett (@terryandrob) March 12, 2015

The End.

— Terry Pratchett (@terryandrob) March 12, 2015