Paris, France (CNN) -- The head of a government laboratory studying genetically modified plants said Monday that activists caused major damage during their weekend attack on a research facility in eastern France.
Before dawn Sunday, about 70 masked activists associated with the European protest movement Faucheurs Volontaires -- or Voluntary Reapers -- pulled 70 experimental grape vines by their roots and chopped them to pieces, said Jean Masson, president of the National Agricultural Research Institute, or INRA, in eastern France.
He estimated the total damage at 1 million euros ($1.28 million).
Police detained about 60 people, questioned them and then released them pending charges.
The vines were part of a transgenic experiment to develop disease-resistant plants at the INRA research station and had been attacked once before by a lone activist.
In a communique, the Faucheurs Volontaires said the grape vines were "neutralized" because "this experimental field was a first step toward imposing this type of agriculture, which is currently forbidden". CNN