Two teenagers were threatened with what police believe to be a hunting knife during an altercation in Stevenage on Saturday.
Police have released pictures of a man they would like to speak to as part of their enquiries following the incident, which happened on a public bridle path off Gresley Way.
Between 4pm and 4.12pm on Saturday, two teenagers were riding dirt bikes when a man entered the path from the housing estate across the road.
He allegedly became agitated with the teenagers for riding their bikes.
After a verbal altercation, the offender threatened the victims with what is thought to be a hunting knife.
When the victims said they were calling the police, the offender walked away in the direction of Walkern and Aston.
The teenagers were physically unharmed.
Police would like to speak to the man pictured as they believe he may have been in the area at the time and have information about the incident.
Anyone who recognises him or has any other information should contact PC Carl Webster by emailing carl.webster@herts.pnn.police.uk, calling the non-emergency number 101 quoting crime reference 41/59314/18 or report information online at www.herts.police.uk/Report.
Alternatively, contact Crimestoppers anonymously on 0800 555 111 or through their anonymous online form at www.crimestoppers-uk.org.
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