A robber threatened a member of staff at a Post Office and stole with cash and stamps.
The culprit made off on a motorbike and police are investigating what happened.
The incident at the Bramcote Lane Post Office, in Wollaton, happened at about 5pm on Wednesday, November 25.
Police said the suspect may possibly have been armed with a weapon.
Officers have launched a witness appeal and have asked any drivers with dashcam footage of the motorbike to get in touch.
Detective Sergeant David Nicks, of Nottinghamshire Police, said: "Thankfully no-one was hurt during this frightening incident but the victim was left very shaken by what happened.
"We believe two people pulled up outside the Post Office on a motorbike before the pillion passenger alighted and entered through the main entrance.
"Did you see these individuals in the area? Did you capture them on your dashcam as they left the scene on the motorbike?"
Anyone with information is asked to contact the force on 101, quoting incident 509 of November 25.
Crimestoppers can be contacted anonymously on 0800 555 111.
