Frustration over cheap Spanish imports spilled into supermarket aisles in southern France after local winemakers wrecked bag-in-box wines brought across the border.

Winemakers staged a protest by destroying Spanish bag-in-box wines at a branch of the Carrefour supermarket near to Montpellier in France’s Languedoc-Roussillon region, according to French media reports.

Tension over cheap Spanish wine imports has reached boiling point in Languedoc as the French presidential election approaches.

Thousands of winemakers marched through the streets of Narbonne in the region earlier this month to complain at the unfair competition that they face from Spain and about the lack of government support for their industry.

Militant winemaker group CAV – or CRAV as it is sometimes known – has attacked lorries carrying Spanish wines and set fire to importers’ offices in the past year.

Languedoc-Roussillon remains France’s largest wine producing region. It continues to produce large amounts of table wine, even if a new generation of producers has also demonstrated some of the area’s high quality potential on certain sites in the past decade.

French supermarkets were not doing enough to inform drinkers about the origins of the wines on their shelves, according to local unions, including the trade body for young farmers and the independent winemakers’ group.

Samuel Masse, president of the youg farmers’ union for the Hérault region, was quote by Agence France Presse as saying that more protests like this one would follow.