A man from Northampton has been arrested by police after allegedly pointing a gun at a driver on the M1 motorway.
Police said the driver of an Audi A3 was left shaken after the driver of a blue Vauxhall Frontera pointed a gun at him on the northbound carriageway between junctions 14 and 15 in Northamptonshire.
The Vauxhall Frontera is believed to have been carrying a large brown dog.
Police said the driver of a blue Volvo car travelling in the same area is thought to have written something down about the incident.
That driver and anyone who may have seen either vehicle before or after the alleged incident are being asked to come forward to speak with officers.