Operation Crucible is a police-led, multi-agency investigation into the organised theft and unlawful trade of metal in England and Wales. Involved agencies include British Transport Police, the Metropolitan Police Service, Hertfordshire Constabulary, Norfolk Constabulary, Suffolk Constabulary, Northamptonshire Police, Leicestershire Police, Essex Police, Cambridgeshire Constabulary, the UK Border Agency, Her Majesty's Revenue and Customs, Trading Standards and the Historic Buildings and Monuments Commission for England.