(37) The Book of Fighting [The Prohibition of Bloodshed]
كتاب تحريم الدم
(22) Chapter: The One Who is Killed Defending His Wealth
(22) باب مَنْ قُتِلَ دُونَ مَالِهِ ‏‏
Sunan an-Nasa'i 4084 
It was narrated that 'Abdullah bin 'Amr said:
"I heard the Messenger of Allah [SAW] say: 'Whoever fights to protect his wealth and is killed, he is a martyr.'"
أَخْبَرَنَا مُحَمَّدُ بْنُ عَبْدِ الأَعْلَى، قَالَ حَدَّثَنَا خَالِدٌ، قَالَ حَدَّثَنَا حَاتِمٌ، عَنْ عَمْرِو بْنِ دِينَارٍ، عَنْ عَبْدِ اللَّهِ بْنِ عَمْرٍو، قَالَ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ ‏ "‏ مَنْ قَاتَلَ دُونَ مَالِهِ فَقُتِلَ فَهُوَ شَهِيدٌ ‏"‏ ‏.‏
Grade :  Sahih (Darussalam)
Reference : Sunan an-Nasa'i 4084
In-book reference : Book 37, Hadith 119
English translation : Vol. 5, Book 37, Hadith 4089