Three knives were stolen by prisoners after they were left unattended by workmen at a secure jail.
The blades were taken at HMP Wayland, a category C prison in Norfolk with a capacity of 1,017 inmates, on Wednesday.
They were recovered in less than five hours after contractors reported them missing.
HMP Wayland, whose previous inmates include Reggie Kray and Westminster Bridge terrorist Khalid Masood, was reportedly put on lockdown while officers searched for the knives.
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A Prison Service spokesman said: “These items were quickly recovered and prisoners engaging in this kind of behaviour can expect punishment.
“The prison will be reminding its contractors of the importance of securing their equipment.”