British Sugar has hired an odour consultant to support their investigation into the strange smell that has puzzled large parts of Norfolk.

The announcement was made by South West Norfolk MP, Elizabeth Truss, after she met with the managing director of British Sugar to discuss whether the company's new operation at Cornerways Nursery, near Wissington, could be the source of the smell.

Ms Truss said: 'The recent harvest of the specialist crop was the first one to come from Cornerways Nursery, near Wissington and with the process generally taking about four to five weeks, there is the potential for strong smells to linger for quite a few days.

'British Sugar have assured me that they do not want to create any problems for local residents and I certainly want to see any changes, where needed, implemented as quickly as possible.

'An environmental specialist and odour consultant have been engaged to investigate the issues raised and if necessary, investment will be made in appropriate odour control equipment. I think everyone recognises the importance of the work done at the factory but it should not adversely impact on the surrounding towns and villages, subsequently I have asked British Sugar to keep me updated on developments.'

People from across the region have been noticing the smell and while descriptions have varied, the majority describe it as being similar to the smell of cannabis.

British Sugar moved away from the production of tomatoes to producing plants for the pharmaceutical sector at the end of 2016 and greenhouses at Wissington now grow a plant that is a member of the cannabis family, used for an epilepsy treatment called Epidiolex.

The harvesting of the first crop took place in June, the same month that people began to pick up on the smell.

However, it is difficult to conclude that there is a single source for the smell. Recent weather reports show that there has been very little wind in the county and despite people reporting it as far as Norwich, there has not been a strong westerly wind to carry it.

Similarly, there have been other reports of the smell having drifted east of Wissington in places such as Cambridgeshire and Peterborough.

The other theories

A large number of theories on what could be the source have emerged, here are a few possibilities.

Mike Scott, a farmer from Wisbeach, said: 'The smell is a particular chemical farmers are using to control the recent increase in aphid numbers, the hot spell caused an explosion of aphid and other pests that cause damage to crops, the scent is harmless but does hang around a bit in certain weather conditions.'

While David Burton, from Whissonsett, said: 'We're subjected to smells throughout the summer from a local herb processing plant, especially when processing the herb coriander which was processed last week. The smell can be so bad all windows and doors have to be closed. It would almost certainly carry across county by prevailing winds.'

It has also been suggested that the smell is related to the police disposing of illegal cannabis crops but Norfolk Constabulary confirmed that incinerations are not done in the county.

More: Mystery of Norfolk smell deepens as British Sugar investigates