Sahih Muslim Book 20, Hadith Number 4607.

Chapter : It is forbidden to take the Qur’an to the land of the infidels when it is feared that it might fall into their hands.

It has been narrated on the authority of Ibn ‘Umar who said: The Messenger of Allah (may peace be upon him) forbade that one should travel to the land of the enemy taking the Qur’an with him.