A 26-year-old man was seriously injured in a collision on the A6 near Desborough.
The man was riding a distinctive orange Yamaha motorcycle heading towards Desborough from Market Harborough on the A6, at around 6.25pm on Sunday (August 25), when the collision took place.
As the motorcycle approached the junction with High Street, the rider lost control of the bike, leaving the main carriageway before colliding with a lamp post.
The motorcyclist sustained serious leg injuries and was taken to Walsgrave Hospital in Coventry by air ambulance.
Northamptonshire Police said they would like to speak to anyone who may have witnessed this incident or who may have any information regarding it.
They would particularly like to speak to the driver of a red car which turned onto the A6 from High Street as the motorcycle was approaching the junction, as they may have witnessed the collision.
Witnesses is asked to phone the Drivewatch Hotline on 0800 174615.