Two men carrying knives, one described as a machete-style weapon, chased a pair of friends from a shop in Northampton.
The victims were approached and confronted by the armed men with a dog outside the Costcutter in Billing Brook Road, Lings, at around 7.20pm on Tuesday (November 26).
They then fled, chased by the suspects and were able to get away unharmed.
The suspect with the dog is described as a black man, 6ft, of slim build and with short black hair.
He wore a green jacket with a grey hoodie underneath, blue tracksuit bottoms and white trainers.
The second suspect is described as white, 6ft, of stocky build with short black hair and a short beard.
He wore glasses, a black jacket with a woolly hood, grey tracksuit bottoms and black shoes.
Anyone who saw the incident or has information about it should call Northamptonshire Police on 101, or Crimestoppers anonymously on 0800 555111.