Some Tim Hortons locations just raised prices — and Canadian customers aren't happy about it.

On Wednesday, a number of Tim Hortons locations increased menu prices, according to Nomura analyst Mark Kalinowski.

"[S]ome have posted signs reading 'To our valued guests, please be aware that due to rising operational costs, there will be a slight price increase affecting some hot beverages and breakfast menu items starting Wednesday, August 2, 2017,'" Kalinowski wrote in a note to investors. "'We greatly appreciate your business and look forward to providing you with the same quality, service and value our guests have always appreciated. Sincerely, Tim Hortons.'"

Tim Hortons customers were not pleased with the news that the Canadian doughnut and coffee chain was raising prices, and took to social media to complain.

—The Book Of Amanda (@MsBlueLipstick) August 2, 2017

"Damn country is about to riot," one person wrote on Twitter. "Nobody is saying sorry for anything."

According to Kalinowski, the price increases will be "quite modest," such as charging 10 Canadian cents more for a cup of coffee.

On Tuesday, Tim Hortons' parent company, Restaurant Brands International, reported that Tim Hortons' Canadian sales fell 0.6% in the most recent quarter.

"Will this menu price increase (minus any accompanying traffic loss) be enough to get Tim Hortons Canada back to positive same-store sales in Q3?" Kalinowski writes. "Probably not in and of itself."

Tim Hortons' sales slump — and Canadian price increases — come at a time when many Canadian franchisees are facing off against Restaurant Brands. In June, a group of Canadian franchisees filed a lawsuit claiming that the company had failed its obligations to local operators.

"You’ve got three or four generations that have been brought up with Tim Hortons," David Hughes, a Canadian franchisee, told Bloomberg. "We were involved in the community. Restaurant Brands, they're not interested in that. All those things that we are famous for — the kids' camps — those are the things that make us different than everyone else."

Franchisees also told Bloomberg that Restaurant Brands was responsible for menu price increases, as the company charged more for supplies, from sugar to items like knives and scissors.

Restaurant Brands CEO Daniel Schwartz emphasized the company's dedication to Canada in a call with investors on Wednesday.

"Both our strong Canadian heritage and our community involvement are two of the most important attributes of Tim Hortons," Schwartz said.