Sahih Muslim 4519
صحيح مسلم#4519SahihIbn 'Aun reported:I wrote to Nafi' inquiring from him whether it was necessary to extend (to the disbelievers) an invitation to accept (Islam) before meeting them in fight. He wrote (in reply) to me that it was necessary in the early days of Islam. The Messenger of Allah (ﷺ) made a raid upon Banu Mustaliq while they were unaware and their cattle were having a drink at the water. He killed those who fought and imprisoned others. On that very day, he captured Juwairiya bint al-Harith. Nafi' said that this tradition was related to him by Abdullah b. Umar who (himself) was among the raiding troops
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 32:1