They can interrupt a witness if the witness is abusing their time. Usually what happens—and I'll remind you of this—is the witness takes the witness position and gives a 10-minute presentation. When it's a minister, sometimes we let it go for 15.
Today the minister chose to speak for 25 minutes, and he was attempting to repeat his propaganda during the member's time. She objected to that. She stopped that. That's absolutely normal, Madam Chair.