"The punishment of those who wage war against Allah and His Messenger, 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 sides, or exile from the land: that is their disgrace in this world, and a heavy punishment is theirs in the Hereafter;" - Quran 5:33 (read more)

"And he [Muhammad] had their hands and feet cut off. Then he ordered for nails which were heated and passed over their eyes, and whey were left in the Harra (i.e. rocky land in Medina). They asked for water, and nobody provided them with water till they died (Abu Qilaba, a sub-narrator said, 'They committed murder and theft and fought against Allah and His Apostle, and spread evil in the land.')" - Sahih Bukhari 1:3:63 (read more)

"If (all types of men) are taken, from the first, and one placed after another, like the Negro from Zanzibar, in the Southern-most countries, the Negro does not differ from an animal in anything except the fact that his hands have been lifted from the earth -in no other peculiarity or property - except for what God wished. Many have seen that the ape is more capable of being trained than the Negro, and more intelligent." - Nasīr al-Dīn al-Tūsī