Sayyiduna Abdullah bin Umar (may Allah be pleased with him) narrates that the Prophet Muhammad (peace and blessings be upon him) said regarding the prayer of fear: The Imam will stand, and a group will stand with him. They will perform one rak'ah, and the other group will remain between them and the enemy. Then those who performed one rak'ah with the Imam will go back, and those who have not yet prayed will take their place. Then these people will come and perform one rak'ah with the Imam. Then the Imam will complete his prayer. Each of the two groups will perform one rak'ah separately. If the fear is more severe than this, then the prayer should be performed while walking or riding.