Workers are walking off the job at Tesla’s gigafactory construction site in Nevada due to the presence of out-of-state workers.

According to Todd Koch, the president of the Building and Construction Trades Council of Northern Nevada, about 100 construction workers that are helping to build the factory near Reno walked off the job earlier this week.

The reason? The workers were upset that Tesla contractor Brycon Corporation is bringing in personnel from New Mexico and Arizona.

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“It’s a slap in the face to Nevada workers to walk through the parking lot at the job site and see all these license plates from Arizona and New Mexico,” Koch said in an interview with Automotive News.

The 10-million square-foot facility will cost $5 billion, and work is proceeding ahead of schedule. Tesla responded to the walkout by sending out a press release saying that the non-union contractor in question, which went unnamed in the release, had hired more than 50 percent of its workforce from Nevada and that over 75 percent of the overall workforce consists of Nevada residents. The company did not comment of how work on the site might or might not be affected.

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“Today’s activity stems from the local Carpenters Union protesting against one of the third-party construction contractors that Tesla is using,” the automaker said in the release. “Their issue is not with how Tesla treats its workers.”

Brycon, which is based in Rio Rancho, New Mexico, did not respond to a request for comment from AN.

A deal that Tesla struck with the State of Nevada in 2014 stipulates that the automaker will get $1.25 billion in tax breaks over the next two decades, and it’s also required to give half of the projected 6,500 permanent jobs that the factory will create.

Automotive News