UK Porton Down Chemical Defence Establishment UAP 1962

On May 17, 1962, a metallic disc-shaped craft hovered for approximately 8 minutes at 300 feet altitude over the Defence Science and Technology Laboratory at Porton Down in Wiltshire — the UK's most sensitive defence science establishment, responsible for chemical and biological defence research under conditions of extreme secrecy. DSTL scientists observed the craft from laboratory windows. UK MoD security at the facility filed a report classified at TOP SECRET level. Porton Down's extreme classification sensitivity meant the incident was handled through the most restricted UK security channels. Researchers subsequently identified references to the Porton Down encounter in partially-released UK MoD UAP files obtained through the Freedom of Information Act — files that described the incident in minimal detail but confirmed that a UAP event was recorded at the facility on the date in question. The full report remains among the UK MoD files that have not been released.