Musnad Ahmad Hadith 10195

It is narrated from Abu Huraira (may Allah be pleased with him) that the Noble Prophet (ﷺ) said: Whoever commits suicide by drinking poison, that poison will be in his hand and he will sip it in the Hellfire, and he will remain there forever. Whoever kills himself with a sharp instrument (commits suicide), that sharp instrument will be in his hand and he will stab it into his belly in the Hellfire, and he will remain there forever. And whoever throws himself down from a mountain and commits suicide, he will keep falling down from a mountain in Hell, and he will remain there forever.