Luke Christopher Horner, based in Amersham, Buckinghamshire, with the Thames Valley force, has been charged with one count of engaging in penetrative sexual activity with a child and one of making an indecent image of a child.

Northamptonshire Police said the charges against the 24-year-old were brought following an incident in Rushden last Sunday "in which a 13-year-old girl was sexually assaulted".

Horner was due to appear at Northampton Magistrates' Court on Friday.

The officer has been suspended from duty and will be the subject of a separate misconduct investigation by Thames Valley Police, who have also referred the matter to the Independent Office for Police Conduct (IOPC).

A Northamptonshire Police spokesman said: "This is a live investigation and therefore the force will not be making any further comment at this time."