A lorry carrying 28 illegal immigrants was discovered in Corby on Saturday (June 17).
The Greek-registered vehicle was making a delivery of Greek yogurt to the Oakley Hay industrial estate when the driver heard knocking noises coming from the back of the refrigerated lorry at about 3.45am.
Police were called and when they opened the lorry up, 28 immigrants, all from Vietnam, were discovered.
Officers provided some welfare assistance to those found in the lorry before representatives from the UK Border Agency took over.
A spokesman for Northants Police said the driver of the lorry was arrested.