If the comments came up as part of the discussion, then I would prefer if the entire class was allowed to comment on the student's views with you, the teacher, as a moderator. I would expect that my professor would know when the discussion was getting out of hand and move on if necessary. I would be more upset/annoyed if the class devolved into an argument between the student and the professor without the rest of the class allowed to participate.
If the offensive views came completely out of the blue, I would prefer if you, the professor, informed the student that he was out of line, told him to stop, and then moved on with the class. If he continued to interrupt, I wouldn't mind if you kicked him out for disrupting the class.
It would be weird if you immediately kicked him out of class for sharing his potentially offensive views. I don't know if you are in the US, but I feel that even people with offensive (to me)
views have the right to share them. It's HOW
they share them, that causes most of the problems