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Today, a Ryanair flight from Lithuania to London Luton was the subject of a presumed hoax, and had some form of security alert. In the incident, it was diverted to Stansted, while being escorted by fighter jets.
What would the escort actually achieve? My best guess is to shoot it down in case of a hijacking, but this seems like a particularly grim prospect and perhaps maybe not one that would be so publicly on display. Is there another reason why it might have been escorted?