I see the phrase on the news, but I don't quite understand on their news in this context. It's from the book Harry Potter.
"You'd be stiff if you'd been sitting on a brick wall all day," said Professor McGonagall.
"All day? When you could have been celebrating? I must have passed a dozen feasts and parties on my way here."
Professor McGonagall sniffed angrily.
"Oh yes, everyone's celebrating, all right," she said impatiently.
"You'd think they'd be a bit more careful, but no — even the Muggles have noticed something's going one. It was on their news."
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