One police officer and five protesters were injured on Saturday when violence broke out during a demonstration in the French grain port of La Rochelle over the construction of large reservoirs to feed agricultural irrigation.

The police fired tear gas, while they tried with water cannons and reinforcements to disperse the approximately 4,000 protesters following the disturbance that broke out in the early afternoon, in which several shops were damaged and at least seven people were arrested.

“A number of radical, far-left participants attacked property,” Interior Minister Gerald Darmanin told X. “It’s hard to see a connection with environmental protection.”

Droughts in France have raised tensions over water resources, and critics say building large reservoirs to feed agricultural irrigation is a wasteful practice that favors big farms.

On Saturday, protesters gathered in front of a site owned by Soufflet Negoce, a grain trading business owned by French cooperative group InVivo, before beginning their march through the city.

In March last year, similar incidents broke out during another demonstration about agricultural reservoirs in Sainte-Soline in western France.

Saturday’s unrest comes as the country has raised its security alert to the highest level ahead of the Olympics, which begin with the opening ceremony on the Seine River on July 26.