Sahih Muslim 140
The Book of Faith
The evidence that the blood of one who aims to seize other people's wealth without right may be shed, if he is killed he will be in the fire, and the one who is killed defending his property is a martyr
Abu Huraira reported: A person came to the Messenger of Allah (ﷺ) and said: Messenger of Allah, what do you think if a man comes to me in order to appropriate my possession? He (the Prophet) said: Don't surrender your possession to him. He (the inquirer) said: If he fights me? He (the Prophet) remarked: Then fight (with him). He (the inquirer) again said: What do you think if I am killed? He (the Prophet) observed: You would be a martyr. He (the inquirer) said: What do you think of him (Messenger of Allah) If I kill him. He (the Prophet) said: he would be in the Fire.