Two men have been jointly charged with conspiracy to blackmail.

The charges relate to a number of offences across the country in which threatening letters were sent to companies linked to drug testing, as well as their business partners and employees.

Robert Griffiths, 59, of Kingsfield Oval, Stoke-on-Trent, and Robert Lewis, 62, of Pheasant Road, Trebanos, Swansea, will appear at Oxford Magistrates’ Court today.