He heard the Messenger of Allah ﷺ, during the Fajr prayer, after raising his head from the bowing in the second rakah, say, "Our Lord, to You belongs all praise." Then he said, "O Allah, curse so-and-so and so-and-so," supplicating against certain hypocrites. So Allah the Exalted revealed, "Not for you, [O Muhammad, but for Allah] is the decision whether He should [cut them down] or forgive them or punish them, for indeed, they are wrongdoers." [Aal Imran 3:128]
حدثنا عبد الرزاق حدثنا معمر عن الزهري عن سالم
أنه سمع رسول الله ﷺ قال في صلاة الفجر حين رفع رأسه من الركعة قال ربنا ولك الحمد في الركعة الآخرة ثم قال اللهم العن فلانا وفلانا دعا على ناس من المنافقين فأنزل الله تعالى {ليس لك من الأمر شيء أو يتوب عليهم أو يعذبهم فإنهم ظالمون}
Its isnad is sahih, and it is a longer version of 5997. See also 5674 and 6346, and the hadith that follows this one. The addition of his saying, "and so-and-so," is confirmed in the margin of ك, marked as a correction, and in the margin of م ع, marked as an alternate reading.