Narrated ‘Aisha:
Some people asked Allah’s Apostle about the fore-tellers He said. ‘ They are nothing” They said, ‘O Allah’s Apostle! Sometimes they tell us of a thing which turns out to be true.” Allah’s Apostle said, “A Jinn snatches that true word and pours it Into the ear of his friend (the fore-teller) (as one puts something into a bottle) The foreteller then mixes with that word one hundred lies.”
Sahih Bukhari, Volume 7, Book71, Number 657