Officers are appealing for witnesses and information following a serious collision on the A405, near Bricket Wood, towards Watford.
The collision happened at around 6.45am yesterday (February 16), and involved one vehicle – a white Mercedes C Class.
For reasons unknown at this time, the vehicle left the carriageway and collided with a bridge.
Despite the best efforts of the emergency services, the man, who was in his 40s, was pronounced dead at the scene.
PS Ian Manley, from the Bedfordshire, Cambridgeshire and Hertfordshire Road Policing Unit, said: “Our thoughts are with the friends and family of the victim at this very difficult time. They are currently being supported by specially trained officers, and we ask that their privacy is respected.
“We are appealing for the public’s help so that we can give them some answers. Did you see the collision, or the events leading up to it? Did you happen to catch any footage on a dash cam?
“If you saw the incident or have any information or dash cam footage that you think could assist our investigation, please get in touch with us as soon as possible.
Anyone with information is asked to contact PS Manley directly via email at email@example.com.
You can report information online at herts.police.uk/report, speak to an operator in our Force Communications Room via online web chat at herts.police.uk/contact or call our non-emergency number 101 quoting reference ‘Op Simper’.
If a crime is in progress or someone’s life is in danger, call 999 immediately.
Alternatively you can call Crimestoppers anonymously on 0800 555 111 or report information online at crimestoppers-uk.org.