Sahih Bukhari
Saying Something under Compulsion (Ikraah)
Volume: 009 / Book Number: 085 / Hadith Number: 75
Narrated Qais:
I heard Sa'id bin Zaid saying, "I have seen myself tied and forced by 'Umar to leave Islam (Before 'Umar himself embraced Islam). And if the mountain of Uhud were to collapse for the evil which you people had done to 'Uthman, then Uhud would have the right to do so." (See Hadith No. 202, Vol. 5)