A man has been arrested following a hit-and-run incident which left a motorcyclist with serious injuries.

Police were called shortly after 6pm on Monday following a crash between a motorbike and a BMW on North Approach near Leavesden.

A rapid response vehicle, two ambulances and the air ambulance from East Anglian Air Ambulance attended the scene.

The rider of the motorcycle - a man believed to be in his 20s - was flown by air ambulance to St George's Hospital in London with suspected serious leg injuries. He remains in a serious but stable condition.

The A405 North Orbital road was closed for a short time so the air ambulance could land.

The BMW was not on the scene when police arrived and was later found unattended.

One man has been arrested in connection with the incident and is currently in police custody. Enquiries are continuing.

Officers are appealing for anyone who witnessed the incident or has information about what happened to please contact the Watford Local Crime Unit via the non-emergency number 101.