Praying behind an imam who has ritual impurity on him, which he is unaware of

Question:
Honorable Shaykh, may Allah grant you success. What about one who prayed behind an imam who had ritual impurity on him, and he did not know about it until he prayed on other days or after a few days?

Answer:
The follower’s prayer is valid, and the imam’s prayer is also valid. He should wash off the impurity if he becomes aware of it while he is in prayer. If he only becomes aware after the prayer, his prayer is valid, and he should wash it off for the future; what has passed is excused. The follower’s prayer is valid. Yes.