A pair of phone shop thieves brandished a knife on a Northampton town centre sales assistant when the brave shop worker tried to confront them.
Detectives want to trace a man and a woman captured in this CCTV image who are believed to have lifted goods from the Carphone Warehouse in Abington Street.
The pair were seen browsing the iPhone demonstration phones on display between 5.41pm and 5.53pm last Wednesday (November 23).
The man managed to remove a black iPhone 7 from its security casing and the pair then left the store. However, when a staff member chased after them, the man pictured then brandished a knife before running away with the woman.
The man was described as white, aged between 25 and 29, 5ft tall, with an average build and short black hair with a parting to the side.
He was wearing a black leather jacket with textured shoulders, light coloured jeans and Timberland-style maroon boots. He spoke with an Eastern European accent.
The woman was white, aged between 19 and 24, 5ft 6 inches and slim, with long, dark hair. She was wearing a parka-style olive jacket, light-coloured jeans and Converse-style shoes.
Witnesses or anyone with information about the incident can contact police on 101 or Crimestoppers anonymously on 0800 555 111.