Sweden has issued international arrest warrants for two Britons suspected of illegally importing 10m euros (£8m) worth of garlic into the EU via Norway. Why would criminals do that?

Swedish state prosecutors claim to have cracked one of Europe's more seemingly strange, if lucrative, smuggling rings.

They say two British men are believed to have made millions of euros smuggling Chinese garlic from Norway into Sweden.

The EU imposes a 9.6% duty on imported foreign garlic.

The supplies are said to have been shipped to Norway - a non-EU state where no garlic import tax is applied - and then smuggled into neighbouring Sweden and the rest of the EU by lorry, thus avoiding EU import duties.

It's not the first time garlic smuggling has made the headlines.

In December 2012, a man from west London was sentenced to six years in jail for smuggling garlic from China into the UK.

The answer EU imposes 9.6% customs duty on foreign garlic

China produces about 80% of the world's garlic, cheaply

Criminals can make millions of euros smuggling it

Murugasan Natarajan, and his assistant Lakshmi Suresh, were convicted of dodging 2.5m euros (£2m) in import duty. They had told officials the garlic was fresh ginger, which is untaxed.

In March 2012, the head of Ireland's largest fruit and vegetable producer was jailed for six years over a 1.6m euros (£1.3m) scam involving the importation of garlic.

Paul Begley, 46, of Rathcoole, County Dublin, avoided paying customs duty on more than 1,000 tonnes of garlic from China by having the shipment labelled as apples.

So when did garlic start attracting criminals?

Pavel Borkovec, from the European Anti-Fraud Office (OLAF), said "fraud and irregularities" with Chinese fresh garlic have occurred since the 1990s.

But he says the real financial implications for the EU budget started in 2001, when by a 9.6% customs duty on foreign garlic - with an additional duty of 1,200 euros per tonne - was introduced.

It was meant to prevent garlic growers in EU member states from being driven out of business by Chinese farmers, who have captured large swathes of the global market by producing crops at knock down prices.

This additional duty of 1,200 euros per tonne is not applicable to imports within an annual quota of 58,870 tonnes worldwide (33,700 tonnes for China).

The history of garlic Garlic originated in Central Asia where it was probably used as far back as Neolithic times as a food flavouring and seasoning

It is mentioned in ancient Egyptian, Greek, Indian and Chinese writings

As a culinary and medicinal plant, it spread in ancient times to the Mediterranean and beyond, and used in Egypt by 3000BC

Also known by ancient civilisations of the Indus Valley - in what is now Pakistan and western India - from where it spread to China

Spanish, Portuguese and French introduced it to the New World Source: Kew Try out some garlic recipes Discover how to use wild garlic

China produced 18,560,000 tonnes of garlic in 2010, accounting for about 80% of the world's output, according to the United Nations' Food and Agriculture Organisation.

Garlic in the EU is mainly produced in Spain, but also in Italy, France, Poland, Hungary, Romania and Bulgaria.

Borkovec says smuggling can cost the EU a "significant" amount.

"One container of fresh garlic represents a potential risk of about 30,000 euros (£24,700) in terms of customs duties," he says.

The "modus operandi" of garlic smuggling from China has developed over years, he says.

"Origin fraud" was a favourite for some time. Chinese garlic would be declared, at import, as originating in countries with whom the EU has preferential arrangements in place, where normal customs duty do not apply.

"For example products originating in Turkey, Mediterranean countries like Egypt, Jordan, Morocco, or some countries in South and Central America, may benefit from an exemption of customs duties or reduced duties," he says.

"Misdeclaration of goods" has also seen fresh garlic declared as frozen or dried garlic, or other commodities such as apples, onions or ginger.

More recently, "real smuggling" - where no declaration at all is made when entering a country - has been occurring, Borkovec says. Garlic is also being cleared for transit through EU territory but unloaded en route to its destination.

Who, what, why? A part of BBC News Magazine, Who, What, Why? aims to answer questions behind the headlines

He says the Norway case was "exceptional, in the sense that the goods were duly declared at customs in Oslo".

"At a later stage the goods were smuggled into the EU territory - no declaration whatsoever was made while crossing the Norwegian/Swedish border," he adds.

OLAF estimates that millions of euros have been lost over the years, "not to mention the indirect losses by means of unfair competition and loss of market share by EU producers".

Most members of the EU have been affected by garlic smuggling in one way or another, according to Borkovec.

But the UK, Poland and Italy seem to be particularly targeted.

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