Ransomware continues to be the United Kingdom’s most prominent cybersecurity threat, and the country can expect to see a surge in destructive attacks in 2023, warns the former head of the U.K.’s national cybersecurity agency.

Oxford University professor Ciaran Martin says that while overall ransomware activities across the world slumped in 2022, attacks are likely to surge in the coming months. He adds that recent hacks against The Guardian newspaper and the British Royal Mail are examples of these early-stage attacks.