It was narrated that Jabir said:
"The Messenger of Allah said: 'When the last people of this Ummah curse the first, (at that time) whoever conceals a Hadith will be concealing what Allah has revealed.'" (Maudu') (ID)
English reference (ID): Vol. 1, Book 1, Hadith 263 (ID)
Arabic reference (ID): Book 1, Hadith 275 (ID)