U.S. fast food workers and their supporters are taking to the streets in nearly 200 cities to demand an increase in wages.

The walkout began Thursday, the largest the industry has ever seen, according to BusinessWeek, and they were also joined by convenience and dollar store workers.

The campaign said that thousands of workers had joined the strike, a small portion of the fast-food industry, but the protests have spread since the effort first began in November 2012 when a couple hundred workers in New York City staged a strike.

Organizers said fast-food workers in more than 190 cities went on strike. Convenience and dollar store workers also went on strike in cities including Philadelphia, Atlanta, and Chicago in rallies involving hundreds of workers. The companies they worked for included dollar stores such as Dollar Tree, Dollar General, Family Dollar and convenience stores such as Sunoco, Shell, and BP.

Workers lay down inside a Speedway store in St. Louis, both seemingly a protest of wages and a protest against the killings of Michael Brown and Eric Garner.

Fast food workers want an hourly wage of $15 and the right to form unions, which would allow them to support their families without having to rely on food stamps.

The Services Employees International Union is backing the effort, which bears similarities to the retail strikes at Walmart that begin in the fall of 2012.

The effort is trying to shut down large numbers of stores with strikes and one-day walkouts involving a minority of the workforce, which campaign organizers believe is more effective in drawing attention to the effort that organizing store-by-store to win unionization elections. Often, even if a union is adopted at a store, the larger chain takes away their franchise status.

Whether it’s working is a difficult question. The campaign claims that things are getting better at individual stores, and there has been a broader push for legislation in cities across the country that would boost the minimum wage. In fact, plans have passed in Seattle and San Francisco that would boost wages to $15 an hour.

However, the fast food industry remains a very powerful one, and it is defiant in the face of the opposition. Industry representatives called the movement a group of “union-led demonstrations,” according to the BusinessWeek report.

The National Restaurant Association said in a statement that unions were attacking the industry, which “provides opportunity to millions of Americans.”