The Answer;
In the name of Allah, Most Gracious, Most Merciful.
Islam strictly prohibits the taking up of arms against a Muslim state to challenge it’s authority and wit and declare war against Islamic law holds such an action is a clear rebellion.
If such conditions are created, then it is the primary responsibility of the Muslim state to take measures to eliminate rebellion with an iron fist and exterminate terrorism so that no individual or group dare destroy the sweat and blood of social harmony of the society, rain the peace and shed innocent blood. Islam does not allow indiscriminate killing even when Muslim armies are engaged in wars against enemy troops. The killing of children, women, the elderly, infirm religious leaders and traders is strictly forbidden/prohibited. Nor can those who surrender their arms, confine themselves to their homes and seek shelter of anyone to be killed, the public cannot be massacred.
Places of worship, buildings, crops and even trees cannot be destroyed. It is not permissible to keep foreign delegates in custody and murder them and other peaceful non Muslim citizens in retaliation for the interference, unjust activities and aggressive advances of their countries.
And Allah(swt) alone knows best.