I wrote to Nafi asking him whether the call to Islam was issued before fighting. He wrote back to me saying that this was the practice in the early days of Islam, and that the Messenger of Allah ﷺ raided Banu al-Mustaliq while they were unaware, with their livestock being watered at the water source. He killed their fighters, took their dependents captive, and on that day captured Juwayriyah, daughter of Harith. Abdullah bin Umar narrated this hadith to me, and he was part of that army.
حدثنا معاذ
كتبت إلى نافع أسأله هل كانت الدعوة قبل القتال قال فكتب إلي إن ذاك كان في أول الإسلام وإن رسول الله ﷺ قد أغار على بني المصطلق وهم غارون وأنعامهم تسقى على الماء فقتل مقاتلتهم وسبى سبيهم وأصاب يومئذ جويرية ابنة الحارث وحدثني بهذا الحديث عبد الله بن عمر وكان في ذلك الجيش
Its isnad is sahih. Muslim related it (2:46) through Salim bin Akhdar and through Ibn Abu Adi, both of them from Ibn Awn, and in al-Muntaqa (4228) it is noted that it is agreed upon [by Bukhari and Muslim]. It will also come again, at length and in abridged form, at (4873) and (5124).Ghaarrun, with the doubling of the raa, is from ghirrah, with a kasrah on the ghayn, meaning heedlessness, that is, they are unaware. See also the History of Ibn Kathir (4:156).