Video: Aerials of homes raided over Islamist terror plot Counter-terror police detained the men, aged 19 to 27, overnight at locations across west London and High Wycombe in the Thames Valley area, Scotland Yard said. Police vehicles and tape could be seen outside two addresses in High Wycombe - in Desborough Avenue and West Wycombe Road - as officers carried out searches of the properties. The arrests comes a few months after the national terror threat level in the UK was raised from substantial to severe, meaning a terrorist attack is "highly likely." This assessment is separate from the evaluation concerning police officers.