The strikers set up picket lines outside many of the city's big name casinos to protest about subcontracting in the industry.

The strike began after a five-year contract between unions and nine of the 12 casinos expired at midnight on Tuesday (0400 GMT Wednesday).

Union officials said they were satisfied with the terms of the latest contract offer, but would not sign unless bosses stopped hiring subcontractors who do not pay union wages.

The casinos employ between 40,000 and 50,000 people, but not all are union members.

Those hit by the industrial action include the Atlantic City Hilton, Tropicana Casino Resort, Caesars Atlantic City Hotel Casino, Trump Plaza, Trump Marina and Trump Taj Mahal.

Broken promises

Union president Bob McDevitt said the casinos failed to live up to the promises made when casino gambling was proposed to New Jersey voters in the 1970s.

Subcontracting "will erode the community and it will make it difficult in the Atlantic City area for workers to feed their families in the way that was promised by the casino industry," he said.

The union represents bartenders, waiters, cooks and other rank-and-file workers. Cashiers and dealers are not affected.

The casinos were expected to close some of their restaurants and use non-union employees to cope with the walkout.

The strike comes as the city gears up for the 79th annual Miss America Pageant, which is set for Saturday.

The contestants, their chaperones and hundreds of visiting pageant fans are staying in the affected hotels.