The Romanian driver of the lorry has been arrested by the French border police who will investigate.
Dave Hutchinson, Border Force Deputy Director for South East & Europe, said: “The dangers of using refrigerated lorries and sealed tankers in this way are self evident. The consequences are potentially fatal."
In 2000, 58 Chinese immigrants died after being sealed into the back of a lorry which was stopped at Dover.
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Friday night's forecast for the west of the region
It's a Bank Holiday weekend, with half term for many. Here's how it's looking on the roads, in the skies, and at getaway hotspots
Friday night's forecast for the east of the region