Two men have been jailed for a combined total of 20 years for their roles in a "simple but ingenious" plot to bring millions of pounds worth of heroin into the UK disguised as baby powder.
The UK Border Agency (UKBA) is examining how 94 parcels were brought into the UK from Pakistan, involving more than £13 million worth of the class A drug.
A judge was told the scheme involved packages first being sent to Pakistan from Bradford, West Yorkshire, addressed to the international cricket stadium in Lahore.
These were then intercepted and had the heroin inserted in Johnson's Baby Powder bottles, before they were returned to a range of addresses in Hull.
Hull Crown Court heard how the clever part of the plot was how the packages were returned "undelivered" to the return addresses in Hull.
It meant the packages were not treated as imports and avoided close attention at the ports.
Today electrician Allan Riley, 53, and unemployed Paul Cahalin, 28, were jailed for nine years and 11 years respectively.
The court heard how the pair were not the masterminds behind the smuggling plot but looked after the Hull end of the operation.
They secured delivery addresses and made sure the parcels were transported to the Wibsey area of Bradford for the next stage of the scheme.
Paul Mitchell, prosecuting, told the court the scheme was "simple but ingenious".
He described how the operation was spotted after postal workers in Hull became suspicious of the large amount of similar parcels.
The charges admitted by Cahalin and Riley related to 28 parcels smuggled into the UK in February and March this year.
They contained more than 18kg of pure heroin with a street value of £4.5 million.
Investigators believe they were just part of a bigger operation which saw 94 packets brought in containing more than £13 million worth of the drug.
The court heard how the address the initial parcels were sent to in Pakistan - "The International Cricket Ground" - did not exist.
This is when the drugs gangs intercepted them and inserted the heroin.
The plot was uncovered after UK Border Agency officers intercepted three parcels that had arrived at Mount Pleasant Postal Depot in London in March this year.
Each was found to contain eight baby powder bottles each filled with heroin totalling 5.68kg.
Officers later found 11 addresses in Hull had received undeliverable parcels from Pakistan, with occupants often being offered £100 by Cahalin to take delivery of the packages.
A search of Cahalin's house recovered a list of the addresses, which he had torn up and thrown in the bin.
These addresses included homes in the Walton Street, Preston Road, Longhill, Bilton Grange, Gypsyville, Orchard Park and Greatfield areas of Hull.
Sentencing the pair, Judge Michael Mettyear said he agreed the plan was "simple but highly effective".
The judge said: "Class A drugs cause great harm in many different ways."
Judge Mettyear heard how Riley, who was recently told he may have bowel cancer and is waiting for the results of tests, had a son who died as a result of heroin addiction.
He told him: "To become involved in this filthy operation is absolutely disgraceful."
The judge added: "You should be ashamed of your involvement in these things."
Cahalin, of Halliwell Close, Hull, and Riley, of Cranswick Grove, Hull, pleaded guilty to conspiracy to supply a controlled substance at a previous hearing.
Speaking after the case, deputy director of UKBA Crime Directorate Jim Jarvie said: "This case shows our officers continue to keep one step ahead of drugs smugglers and their attempts to evade our checks. The message is clear: we will catch you and when we do you'll go to jail.
"Our officers work round the clock and use the latest technology, intelligence and detection techniques to disrupt the criminal gangs that seek to profit from the vile trade of drug smuggling.
"The length of the sentences handed down today reflects the punishments those trading this harmful drug can expect to face."
Asked how unusual this "return to sender" smuggling method was, Mr Jarvie said: "I think it's the first time it's happened with this significant amount of heroin. I think we've nipped this in the bud and we're now aware of this particular method of smuggling."