Customs officials at Delhi's international airport got more than they bargained for when they found 16 kg (35 lbs) of gold in the nappies of two babies being brought through customs. Two sets of couples, who had brought the babies to the country from Dubai , were arrested.

The groups had arrived at Indira Gandhi International Airport from Surat at 7am on Monday (12 December) and were passing through the green channel.

The gold, worth an estimated £500,000 ($633,000) was in the form of 16 gold "biscuits", each weighing one kilogram which had been put in the nappies of the babies.

More from IBTimes UK

An airport official quoted by Tribune India said: "Gold biscuits weighing about 16 kg have been recovered from the passengers. The sixteen gold biscuits, of one kg each, were found cleverly concealed in the diapers and towel of the two babies they were carrying. The two groups comprising a couple and a baby each are from Surat."

The four adults were being interrogated by customs officials, the Business Standard reported.

It is not the first time nappies have been used to smuggle unusual items. Police in the Australian city of Adelaide found that a Hong Kong syndicate had been using nappies and stuffed toys to smuggle crystal methamphetamine into the country, the Federal government reported.

Tour de France champion Sir Bradley Wiggins told the BBC radio programme Desert Island Discs that his late father smuggled drugs in Bradley's nappies when he was a baby. Nappies are also reportedly used to smuggle drugs into UK prisons.

Gold nugget
16 kg of gold was found in the nappies of 2 babies at a Delhi airport Getty images