Three people were injured and around 100,000 litres wine destroyed when militant winemakers descended on Sète and Montpellier in the early hours on Tuesday.
In Montpellier, ten balaclava-clad protesters wielding baseball bats and sledgehammers attacked the local offices of Onivins, France's national wine trade body. Computers and furniture were destroyed and three employees were injured.
Further south, in the town of Sète, around 50 similarly-armed winemakers attacked an export depot, smashing open the valves of wine storage tanks spilling 100,000 litres of French wine onto the tarmac.
Although the attacks bear hallmarks of the militant group CRAV, which earlier this year carried out a number of violent assaults including a dynamite attack on La Baume winery in the Languedoc, no group has claimed responsibility.
Both attacks were committed overnight. Agriculture minister Dominique Bussereau called them 'cowardly' and 'inexcusable'.
'These actions can only harm the image of the winemakers,' he said.
Denis Verdier, Onivins president and head of the Confederation of French Winemaking Cooperatives (CCVF) said the situation was 'explosive'.
The CRAV (Comité Régional d'Action Viticole) is a group of disaffected winemakers which, after several years' hiatus, re-emerged this year. The group is unhappy with the support struggling winemakers have received from the goverment.
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