These are the shocking images of a robbery in progress at a St Albans convenience store.
It happened at Oaklands Stores on Hatfield Road, St Albans, just after 8.30pm on Thursday, September 5.
An armed man entered the store and shouted at the shopkeeper to give him money. No cash was handed over and the male left.
Detective Constable Jess Berg said: "Thankfully nobody was injured during this incident and nothing was taken, however the victim has, understandably, been left shaken by this.
"We are trying to identify the male pictured in the CCTV images. While the pictures do not show much of the suspect's face, they do show the clothing, his build and the shape of the distinctive weapon being held.
"If you think you recognise this person please get in touch with us."
Report information online at herts.police.uk/contact or call 101 quoting reference 41/80735/19.
Alternatively, you can stay anonymous by contacting the independent charity Crimestoppers on 0800 555 111.
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