A bus driver was threatened by a motorist following an altercation on the A1(M) near South Mimms last month.
The incident occurred at around 12.50pm on Saturday, June 17, on the southbound slip road at Junction 1, just before the traffic lights on the roundabout.
A man exited a red BMW and made verbal threats against a bus driver while the vehicle was stationary.
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"Our enquiries are continuing and we are appealing for anyone with information to please get in touch," PC Emma Gower, investigating.
"Were you driving in the area at the time and saw what happened? We believe there were several other drivers that were stationary on the slip road at the time and may have saw something.
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"Additionally, if you have a dash cam fitted please check it as you may have recorded some crucial footage to assist our investigation."
Anyone with information is asked to please email PC Gower at emma.gower@herts.police.uk.
You can report information online at herts.police.uk/report, via online web chat at herts.police.uk/contact, or by calling the non-emergency number 101, quoting crime reference 41/48675/23.
Alternatively, contact Crimestoppers anonymously on 0800 555 111 or online at crimestoppers-uk.org.
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