Casino resorts in Las Vegas could see tens of thousands employees walk off the job after Culinary Union members voted Tuesday to authorize a citywide strike.

Some 25,000 members of Culinary Workers Union Local 226 and UniteHere Bartenders Union Local 165 participated in two voting sessions at the University of Nevada, Las Vegas Tuesday to authorize the strike any time after June 1, with 99 percent voting “yes”.

Union contracts covering 50,000 union workers expire on June 1 at 34 casino resorts on the Las Vegas Strip and Downtown Las Vegas, including properties operated by MGM Resorts International, Caesars Entertainment Corporation, Penn National, Golden Entertainment and Boyd Gaming, among others.

The 50,000 hospitality employees who are preparing to go out on strike include bartenders, guest room attendants, cocktail servers, food servers, porters, bellmen, cooks and kitchen workers.

“A strike is a last resort. We want to come to an agreement, but the union and workers are preparing for a citywide strike if contracts are not settled by June 1,” said Geoconda Argüello-Kline, secretary-treasurer for the Culinary Union. “We support innovations that improve jobs, but we oppose automation when it only destroys jobs. Our industry must innovate without losing the human touch. That's why employers should work with us to stay strong, fair and competitive.”

The Culinary and Bartenders unions are negotiating new contract language to provide greater measures of security for members including issues that surround workplace safety, sexual harassment, subcontracting, technology and immigration--specifically protection for immigrants with temporary status.

“I voted yes to go on strike to ensure my job isn’t outsourced to a robot,” said Chad Neanover, a prep cook at Margaritaville, a Caesars Entertainment property. “We know technology is coming, but workers shouldn’t be pushed out or left behind. Casino companies should ensure that technology is harnessed to improve the quality and safety in the workplace, not as a way to completely eliminate our jobs.”

According to the Las Vegas Review-Journal, Las Vegas union workers have struck at several casinos over the years, but the last citywide strike was in 1984. That strike, which included about 17,000 workers, impacted 32 resorts and lasted 67 days, costing casinos as much as $100 million in revenue (estimated to be about $250 million today) while city and state budgets lost millions in tourist-related taxes, as noted in the book Vegas at Odds: Labor Conflict in a Leisure Economy, 1960-1985, authored by James Kraft. According to the Associated Press, union members lost an estimated $75 million in wages.

More recently, union members have voted to strike several times in past years, but the last citywide vote was in 2002. In that case, a settlement was reached to avoid a strike.

The Culinary Union was part of one of the longest strikes in the country from 1991 to 1998 against the Frontier hotel-casino, according to the UNLV Libraries. About 550 workers took part in an around-the-clock picket outside the Frontier.