He woke up during the day in Ramadan and found that he was emitting maniy (semen), and he does not know whether it was a wet dream or masturbation; what is the ruling on his fast?

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Check below answers in case you are looking for other related questions:
She is menstruating and is asking him to touch her private part when he is fasting
Delaying ghusl from janaabah in Ramadaan until the sun has risen does not invalidate the fast

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Related Answers:
The one who cannot help vomiting does not have to make up the fast
Suhoor is not a condition for fasting to be valid
Perfume spray reaches his throat without any intention on his part
She is menstruating and is asking him to touch her private part when he is fasting
Delaying ghusl from janaabah in Ramadaan until the sun has risen does not invalidate the fast

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