Sayyiduna Anas bin Malik (may Allah be pleased with him) narrates from the Prophet (peace and blessings be upon him) that he (peace and blessings be upon him) said: "Whoever is killed (unjustly) while defending his wealth is a martyr."
Hadith Referenceالمعجم الأوسط / باب الألف / 1629
Hadith Takhrij«أخرجه الضياء المقدسي فى «الأحاديث المختارة» برقم: 2299، والبزار فى «مسنده» برقم: 6392»