The Messenger of Allah ﷺ led the prayer of fear on one of his days. One group stood with him while another faced the enemy. He prayed one rakah with those who were with him, then they left and the others came, and he prayed one rakah with them. Then each of the two groups completed the remaining rakah on their own.
حدثنا يحيى بن آدم حدثنا سفيان عن موسى بن عقبة عن نافع
صلى رسول الله ﷺ صلاة الخوف في بعض أيامه فقامت طائفة معه وطائفة بإزاء العدو فصلى بالذين معه ركعة ثم ذهبوا وجاء الآخرون فصلى بهم ركعة ثم قضت الطائفتان ركعة ركعة
Its isnad is sahih. Muslim reported it, 1:230-231, from Abu Bakr bin Abu Shayba, from Yahya bin Adam, with this isnad. Its meaning has already appeared in a similar, longer form through other routes at 6259, 6351, 6377, 6378, and see 6194.