US workers accused fast-food giant McDonald's Thursday of systematically stealing wages through illicit practices like shaved hours and unpaid overtime.

Seven class-action lawsuits were filed Wednesday and Thursday in California, Michigan and New York demanding that McDonald's pay back the stolen wages and end the practices that violate state and federal laws, workers and their lawyers said.

McDonald's Corporation is named in all seven lawsuits, while franchisees were included in five of them.

The lawsuits argue that McDonald's, which took in nearly $5.6 billion in profits last year, regularly fails to compensate its already low-paid workers for all the hours they work.

It allegedly forced employees to work off the clock, failed to pay them overtime, shaved hours off time cards, and deprived employees of timely meal and rest breaks, among other practices.

"We've uncovered several unlawful schemes, but they all share a common purpose -- to drive labor costs down by stealing wages from McDonald's workers," Michael Rubin of Altshuler Berzon, who filed the California suits, said in a statement.

"These suits have been filed to stop this widespread employee pay theft," Joseph Sellers, of Cohen Milstein Sellers & Toll, co-counsel in the lawsuits filed in California and New York, said in a conference call announcing the legal action.

Sellers said the suits in three states cover more than 30,000 McDonald's workers. "There may be more suits coming," he said.

McDonald's spokeswoman Gidi Sa Shekhem said the company was currently reviewing the allegations in the lawsuits.

"McDonald's and our independent franchisees are committed to undertaking a comprehensive investigation of the allegations and will take any necessary actions as they apply to our respective organizations," she said in an email to AFP .

Shares in Dow member McDonald's slid 1.4 percent to $97.30 in afternoon trade in New York.