More than 20 aircraft across Europe have been targeted by bomb threats. It's the second time this week, which the UK has called a "malicious hoax". This was reported by Qazaqyia.kz citing BBC News.

BBC Verify has been analysing the messages sent by an aircraft to find out what happens when a flight receives a bomb hoax - as Thomas Copeland explains.

Additional reporting by Emma Pengelly. Produced by Aisha Sembhi. Graphics by Mesut Ersoz and Sally Nicholls.

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