Gloucestershire Police said several men were arrested on suspicion of offences under the Explosives Act early Sunday morning, a major incident was declared after police discovered unexploded ordnance near the village of Whelford, 4 km from RAF Fairford.
Residents within a 1 km radius were evacuated to Cirencester Leisure Centre while a cordon was established and a Hazardous Area Response Team, along with an Army explosive ordnance disposal unit, inspected three vehicles suspected of carrying explosives.
RAF Lakenheath, the closest US base, was placed on Charlie alert, the second‑highest threat level, and RAF Fairford was temporarily elevated to Delta, the highest alert status, by the US Department of Defence.
A US Air Force spokesperson said personnel at RAF Fairford remain vigilant but declined to disclose specific protective measures, adding that the 501st Combat Support Wing would implement appropriate safeguards for service members, civilians and contractors.
Defence Secretary Wes Streeting thanked emergency responders for their swift action and assured the public that the investigation was under control, while a government spokesperson praised the teams but said further comments were premature.
Police have yet to disclose the exact number of suspects or whether the incident is linked to the US base, and counter‑terrorism police are leading the inquiry while the next steps will involve reviewing force protection protocols.