A 28-year-old man died this morning after the car he was travelling in crashed into a tree near Batford.
The man was sitting in the rear passenger seat of the Volkswagen Golf when it came off Lower Luton Road at about 5.25am.
The driver and three other passengers received injuries, although they are not believed to be serious.
Sergeant Colin Jenkinson, from the Road Policing Unit, said: “We’re thoroughly investigating the circumstances of this tragic collision and I’m asking for the public’s help.
“I’d like to speak to anyone who was travelling along the Lower Luton Road this morning and saw the black Volkswagen Golf prior to the incident, or anyone who saw the collision occur. Please contact us, your information could be extremely useful to the investigation.”
The road is currently closed in both directions and at the junction with Bowers Heath Lane.
Anyone with information should contact Hertfordshire Constabulary on 101.