There were two knife-point robberies within a week in a town centre shop.
The robber – described as white, aged in his 20s, of broad build and around 5ft 9in tall – targeted Tesco Express in Marlowes, Hemel Hempstead, between 8pm and 8.30pm both times.
He first struck on Wednesday, November 14 and then on Tuesday, November 20. The thief brandished a small knife and ordered staff to hand over cash.
Anyone with information should call Herts Police on 101 quoting reference D1/12/6834 or Crimestoppers anonymously on 0800 555 111.