A French supermarket chain could be fined up to €350,000 after competition investigators found that it broke rules with its insane discounts on products like Nutella.

The 70 percent discounts at the end of January led to tumults among shoppers trying to furiously grab jars of Nutella, a household favourite in France. Footage of the pandemonium in the Intermarché stores went viral on French social media.

The French Ministry of Economy (DGCCRF), competition and anti-fraud agency found that supermarket chain Intermarché infringed a French law that forbids retailers from selling products below their real cost.

In France, retailers are only allowed to sell below price during annual sales and on products they have had in stock for at least one month.

The promotions also covered Procter & Gamble’s, Pampers, Nestle's Perrier sparkling water and Lavazza's Carte Noire coffee, the DGCCRF said.

Intermarché's discounting in this case risked a potential fine, junior economy minister Geny-Stephann told RTL radio.

Intermarché chairman Thierry Cotillard defended the company decision in an interview with newspaper Le Journal du Dimanche, saying that the price offer was made during its official winter sales period.

A judge will now consider the case and decide whether to impose a fine.