Security around an experimental crop in a Hertfordshire field has been stepped up to prevent any damage during a day of action by campaigners.
Those protesting against the genetically modified wheat are being kept away from the Harpenden test site, run by Rothamsted Research.
They are concerned about potential contamination from the cereal:
Security has been increased around a farm in Hertfordshire where Genetically Modified wheat is being grown.
Campaigners planning to protest about the potential dangers of the experimental crops are being kept away from the crop at the Rothamsted Research centre.
Anti GM group "Take the Flour Back" is worried about contamination to the surrounding area. Rothamsted Research says the possibility of contamination from pollen blown in the wind is small.