A yogurt price-fixing cartel in France has been brought down because General Mills blew the whistle.

French yogurt executives colluded over cigarettes and coffee according to a ruling from France's competition authority, who fined 11 dairy companies as much as 56 million euros each for price fixing.

The investigation found that yogurt executives met at cafes and apartments from 2006 to 2012 setting prices for products that made up more than 90 percent of the French market.

Company bosses sketched out secret deals in hotel rooms and on special phone lines created to avoid detection. Sometimes they'd meet at Au Chien Qui Fume, an iconic Paris cafe, one boss is quoted in the investigation documents as saying. His counterparts then "came to my apartment a few times to continue the conversation and smoke a cigarette," he added.

A Yoplait executive used a special cell phone dedicated to the cartel, paid for by Yoplait but not officially linked to him in any way. An executive with dairy maker Senagral used a special cell phone taken out in his girlfriend's name.

The ruling describes how the companies were facing rising milk and packaging costs, and hints at some desperation. One executive lamented in a text message a "totally crazy price" at one supermarket, saying he needed a higher price or else "I'll sink!!!"

General Mills spokesman Tom Forsythe says the company found out about the price fixing soon after the 2011 acquisition of a majority share of Yoplait.

"When General Mills learned of these past practices, we brought the matter to the authorities, cooperated fully and put the practices to an end," he said.

Because of the assistance from General Mills, Yoplait escaped a fine. Several other companies have said they'll appeal their penalties.

The Associated Press contributed to this report.