Detectives investigating a robbery at a shop in Ilkeston believe people in neighbouring counties may have information which could help the inquiry.
Three men have been arrested on suspicion of the robbery; one aged 35 and from Ilkeston, one aged 26 and from Loughborough; and one aged 33 and from Strelley in Nottinghamshire. They have been questioned and released on bail while the inquiry continues.
Detectives are now asking people in neighbouring counties to view footage of the robbery to see if they recognise the men involved.
The footage shows the men use a Ford Mondeo to ram the shutters at the Post Office, in Little Hallam Lane, before entering the shop.
They struggled with a member of staff, who tried to stop the gang, but they made off with an empty cash cassette from the ATM machine, which was being refilled at the time.
The robbery happened at 9.10pm on Friday, October 25.
Anyone with information, or who can help identify the men in the footage, should call Derbyshire police on 0345 123 3333 or Crimestoppers on 0800 555 111.