What is the ruling if one prays behind an imam who has ritual impurity on him, and the one praying behind him knows this?

The questioner : He prayed behind one who was in a state of ritual impurity, and he knew that there was ritual impurity on him. From the house, my son.

The Shaykh : The one praying behind the imam knew that the imam had ritual impurity on him and prayed behind him.

The questioner : According to the school of thought, their prayer remains valid. Their prayer.

The Shaykh : Yes, according to the school of thought, his prayer is invalid. And the second opinion.

The questioner : The second opinion is if the prayer has ended.

The Shaykh : No, of course, he finished and said the closing salam, and the prayer ended, but the imam was ignorant and did not know about the impurity until after he had prayed, and the one praying behind him informed him. According to the second opinion, the prayer is valid because the imam is excused due to his ignorance, and the one praying behind him believes that the imam’s prayer in this state is valid because he is excused by ignorance, so he followed a person whose prayer is valid.

The questioner : Turkey.

The Shaykh : Is this clear? Okay.