A garlic smuggler has been jailed for six years after evading some £2 million in customs duty while importing Chinese garlic.

Murugasan Natarajan, who is now on the run, claimed he was importing ginger, but HM Revenue and Customs (HMRC) investigators found that the containers used were transported at the wrong temperature.

HMRC had launched an investigation into 57-year-old Natarajan, who owned London-based Perfect Imports & Exports Ltd, and his assistant, 28-year-old Lakshmi Suresh, after UK Border Agency officers found more than 7,000 tonnes of garlic. This was in addition to the load disclosed for duty purposes – equalling almost £9,000 of unpaid duty.

HMRC later checked shipping records and discovered that imports of garlic had stopped but imports of fresh ginger – which are free of duty – had increased fivefold. Further checks showed that the temperature in the containers was too cold for ginger, but ideal for garlic.

Natarajan was arrested in April 2011 and was tried in his absence after failing to surrender to bail.

Peter Millroy, assistant director of HMRC criminal investigation, said: “The penalty imposed on Natarajan is the longest sentence in the UK in recent years for the evasion of customs duty. Over 100 containers were identified where there were strong grounds to believe that the contents had either been understated or wrongly described. These rules are designed to protect legitimate businesses from unfair competition.”

During a search of Natarajan’s property, almost £150,000 in cash was seized under the proceeds of crime act. In sentencing Natarajan, His Honour Judge Worsley QC said he had played a leading role from the outset, describing the fraud as being “sophisticated, persistent and prolonged”.

Anyone with any information of the whereabouts of Natarajan should contact HMRC’s fraud hotline on 0800 595 000.

Natarajan of West Drayton in west London, failed to surrender to bail and was tried in his absence at the Old Bailey and on 7 December the jury returned a verdict of guilty and sentenced him to six years imprisonment.

On 22 November Suresh of Hayes, Middlesex pleaded guilty to her role in the fraud and was sentenced to a term of 12 months imprisonment, suspended for 12 months and she was also ordered to pay £10,000 compensation to HMRC.