Salatul Khawf ( https://www.al-feqh.com/en/salat-of-those-with-excuses-recognized-by-the-sharia" rel="nofollow - Salat during Fear)

Salat al Khawf is permissible in every legitimate war at home (residence) or on a journey.

The Description of the Prayer at the time of Fear

Fear does not affect the number of rak’ah to be offered. If it is to be observed while a person is not traveling, it is observed in its usual (complete) form; but it is shortened if on a journey.

-Its permissibility is indicated in both the Qur’an and the Sunnah:

-Pertaining to the Sunnah is the action of the Messenger of Allah ﷺ where he observed it (Salat al Khawf) together with his companions, and the companions observed it after him.

source: https://www.al-feqh.com/en