If a fasting person swallows some of the food remnants in his mouth, does it invalidate his fast?

The questioner : You say: If a fasting person swallows some of the food remnants in his mouth, does it invalidate his fast?

The Shaykh : If that happens without his intention, his fast is not invalidated. Or if he swallows it thinking that it does not break the fast, his fast is not invalidated.
As for if he knows that it breaks the fast and swallows it intentionally and deliberately, he is sinful if the fast is obligatory, and he must make it up. As for if it is voluntary, he is not sinful, but his fast for that day is not valid.