The Repentance - 9:5
When the holy months are over, kill the pagans wherever you find them (if they still refuse to make peace). Seize them, encircle them and watch their every move. If they repent and pray and pay zakat, then let them go free. Allah is Forgiving, Merciful.
Related:
The Cow/2:190
Fight those who fight you in the way of Allah. Do not be aggressive. Allah does not love the aggressors.
The Cow/2:191
Fight them wherever you meet them and drive them out from wherever they drive you out; oppression and torture are worse than killing. Do not fight them unless they fight you near the Holy Mosque. If they attack you, attack them back. Such is the punishment of the disbelievers.
The Cow/2:192
If they cease, Allah is Forgiving, Merciful.
The Cow/2:193
Fight them until oppression and torture cease and the religion is for Allah. If they cease, then there is no enmity for anyone except the wrongdoers.
The Cow/2:194
The holy month can only be observed on both sides. The observance of the truce is mutual. If they attack you, attack them in kind. Listen to Allah and know that Allah is with the righteous.
The Women/4:90
Except those who join a community with whom there is a treaty between you, or who come to you distressed in their breasts because of fighting you or their own people... If Allah had willed, He would have made them to fight against you and they would have fought against you. But if they leave you alone and do not fight you and offer you peace, Allah will not allow you to attack them.
The Heights/7:33
"Say: "My Lord has forbidden only the open and the secret of evil deeds, and sins, and wrongful aggression, and associating partners with Allah what He has not given them any authority or power, and saying about Allah what you do not know."
The Repentance/9:12
If they break their covenant after they have made a covenant and attack your religion, fight the leaders of disbelief, for their covenant is null and void. Perhaps they will desist.
The Repentance/9:13
Are you not going to fight against the people who break their covenant and attempt to drive out the messenger and are the first to start (war) with you? Or do you fear them? It is Allah whom you should fear if you believe.
The Repentance/9:123
O you who believe, fight the disbelievers who surround you and attack you. Let them find firmness in you. Know that Allah is with the righteous.