Surah Al-Baqarah (The Cow), Verse 191

وَاقْتُلُوْهُمْ حَیْثُ ثَقِفْتُمُوْهُمْ وَاَخْرِجُوْهُمْ مِّنْ حَیْثُ اَخْرَجُوْكُمْ وَالْفِتْنَةُ اَشَدُّ مِنَ الْقَتْلِ وَلَا تُقٰتِلُوْهُمْ عِنْدَ الْمَسْجِدِ الْحَرَامِ حَتّٰی یُقٰتِلُوْكُمْ فِیْهِ فَاِنْ قٰتَلُوْكُمْ فَاقْتُلُوْهُمْ كَذٰلِكَ جَزَآءُ الْكٰفِرِیْنَ ۟

Waqtuloohum haisu saqif tumoohum wa akhrijoohum min haisu akhrajookum; walfitnatu ashaddu minal qatl; wa laa tuqaatiloohum 'indal Masjidil Haraami hattaa yaqaatilookum feehi fa in qaatalookum faqtuloohum; kazaalika jazaaa'ul kaafireen

“And slay them wherever ye catch them, and turn them out from where they have Turned you out; for tumult and oppression are worse than slaughter; but fight them not at the Sacred Mosque, unless they (first) fight you there; but if they fight you, slay them. Such is the reward of those who suppress faith.”

Quran 2:191 (Yusuf Ali Translation)