Prescribed Punishments (Kitab Al-Hudud)
Dawud :: Book 38 : Hadith 4359
Narrated Abdullah ibn Abbas:
The verse "The punishment of those who wage war against Allah and His Apostle, and strive with might and main for mischief through the land is execution, or crucifixion, or the cutting off of hands and feet from opposite side or exile from the land...most merciful" was revealed about polytheists. If any of them repents before they are arrested, it does not prevent from inflicting on him the prescribed punishment which he deserves.