It is narrated from Sayyiduna Sa'id bin Zayd (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "Whoever is killed defending his property is a martyr; whoever is killed defending his family is also a martyr; and whoever is killed defending his own blood is also a martyr."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب صلاة الخوف / 6062