It wasnarrated from Ibn 'Umar that the Messenger of Allah (ﷺ) usedtoforbid traveling with the Qur'an to the land of the enemy, lest theenemy gets hold of it. (FR)
English reference (FR): Vol. 4, Book 24, Hadith 2880 (FR)
Arabic reference (FR): Book 24, Hadith 2990 (FR)