The machine can scan a cargoload in an hour

It would take 45 minutes manually to check an average cargo container by hand for illegal tobacco or explosives.

The American-made scanner can look at a series of 25 cargo containers in less than an hour.

The scanner is already used at docks in the UK to check lorries entering the country from Europe or other regions

Cocaine found

The machine was used to discover hidden cocaine in a shipment than might otherwise have gone undetected.

John Powell of customs and excise said: "It has been very successful in Dover and other ports.

"We have seized millions of cigarettes and masses of class A drugs such as heroin and cocaine using the scanner."

Another 20 scanners will arrive at other regional airports across the country in the near future.