Driver arrested after suspected hit and run death
The driver, 28, from Leicester, was arrested on suspicion of causing death by dangerous driving and failing to stop at the scene of a road traffic collision.
He was taken into custody for questioning.
The Bedfordshire, Cambridgeshire and Hertfordshire Road Policing Unit, appealed for anyone with information, saw what happened, or has dashcam footage to get in touch.
Police also thanked the public for its patience when the road was closed while investigations were being carried out.
The northbound carriageway was closed from the discovery of the body until about 20:30 that Monday.