The imam remembering a state of ritual impurity after the prayer with the congregation

Question:
Honorable Shaykh, if the imam prays with the people and then remembers that he was not in a state of ritual purity, or that he became ritually impure during the prayer, is it obligatory for the followers to repeat the prayer, or does one of them complete it for them?

Answer:
If the one praying with the people remembers that he was not in a state of ritual purity, that he was not in wudu', he leaves and one of the followers takes his place to complete the prayer with them. If he starts the prayer with them anew, that is more cautious. To avoid the difference of opinion, he should start the prayer with them anew. The substitute starts the prayer with them anew. If he completes it, his prayer is valid. This is if he entered the prayer without being in a state of ritual purity, or if he entered it in a state of ritual purity but his wudu' was broken during it. He appoints a substitute to pray. It is better for the substitute to start the prayer anew. It is more cautious to avoid the difference of opinion.
As for if he prayed with them and finished, and he did not remember that he was not in a state of ritual purity until after he had finished the prayer, their prayer is valid. He repeats the prayer for himself only. His prayer is not valid, but the prayer of the followers is valid if he did not remember until after he had finished the prayer. If there is impurity on the garment and he forgot it and did not know of it, or did not remember it until after he had prayed, the prayer is also valid. Yes.