Hadith 4:71
Ibn ‘Abbas reported God’s messenger as saying, “Dying abroad is treated as martyrdom." Ibn Majah transmitted it.
وَعَنِ ابْنِ عَبَّاسٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «مَوْتُ غُرْبَةٍ شَهَادَةٌ» . رَوَاهُ ابْن مَاجَه
Original Reference: Mishkat al-Masabih 1594