Police have launched an investigation after a man in his 70s died in a serious crash near London Colney this morning (Wednesday 4 August).

It happened just before 5.30am at the London Colney roundabout on the A414, and involved one vehicle – a black Mercedes.

There were road closures on the roundabout itself, as well as the A1081 and White Horse Lane, and motorists were advised to find alternative routes.

Sergeant Sam Cordingley, from the Bedfordshire, Cambridgeshire and Hertfordshire Road Policing Unit (BCH RPU), said: “We are working to establish the cause of this collision and are appealing to anyone who may have witnessed it to please come forward and speak to us.

Man in 70s dies in crash by roundabout 

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“It happened on a main arterial route and consequently the road closures are causing significant traffic congestion, so we thank motorists for their patience while we work at the scene with our emergency service colleagues.

“If you have a dash cam fitted to your vehicle and you were travelling on the A414 in the direction of Hatfield at the time of the collision, please review your footage and get in touch if you believe you have captured a black Mercedes."

It is currently unclear if anyone was injured.

You can report information online at herts.police.uk/report, talk to one of our Force Communication Room operators via web chat at herts.police.uk/contact, or call our non-emergency number 101 quoting Operation Lantana.

For live updates see our blog.