It is narrated from the grandmother of Sulayman bin Amr bin al-Ahwas (may Allah have mercy on him), Umm Jundub al-Azdiyyah (may Allah be pleased with her), that the Prophet (peace and blessings be upon him) came while the people were crowding one another at the Jamrah or the Jamarat, and he (peace and blessings be upon him) said: "O people, do not destroy yourselves, and stone the Jamarat with pebbles the size of small flicking-pebbles."
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 21847