Sahl bin Abi Hathmah said about Salat al-Khawf that the imam should pray with one group while another group stands facing the enemy. Then the imam should lead the group with him in one rak'ah of prayer, after which this group should go to the place of the group facing the enemy, and that group should come and pray one rak'ah with the imam. Then each group should complete one rak'ah on their own.