Namaz e Khauf

When you (O Messenger Muhammad SAW) are among them, and lead them in As-Salât (the prayer), let one party of them stand up [in Salât (prayer)] with you taking their arms with them; when they finish their prostrations, let them take their positions in the rear and let the other party come up which have not yet prayed, and let them pray with you taking all the precautions and bearing arms. Those who disbelieve wish, if you were negligent of your arms and your baggage, to attack you in a single rush, but there is no sin on you if you put away your arms because of the inconvenience of rain or because you are ill, but take every precaution for yourselves. Verily, Allâh has prepared a humiliating torment for the disbelievers

An-Nisa 102