Sunan At-Tirmidhi
Hadith #1421
Narrated Zaid:that he heard the Messenger of Allah (ﷺ) saying: ""Whoever is killed over his wealth then he is a martyr, and whoever is killed over his religion, then he is a martyr, and whoever is killed over his blood, then he is martyr, and whoever is killed over his family, then he is martyr