A robber stole cash from a shop in Heanor.
At about 10.45pm on Friday, a man entered Heanor Convenience Store, in Holbrook Street.
He threatened the shopkeeper and demanded cash.
He left the shop with cash from the till.
The shopkeeper was unhurt.
The robber is described as white, 5ft 6in and stocky.
He wore dark clothing and had a scarf over his face.
Anyone with information is asked to call police on 101 or Crimestoppers on 0800 555 111.