(GUARDIAN) — As Amazon’s workforce has more than doubled over the past three years, workers at Amazon fulfillment center warehouses in the United States have started organizing and pushing toward forming a union to fight back against the company’s treatment of its workers.

Amazon’s global workforce reached more than 613,000 employees worldwide according to its latest quarterly earnings report, not including the 100,000 temporary employees the company hired for the holiday season.

Just a few months after Amazon opened its first New York-based fulfillment center in Staten Island, workers announced on 12 December the launch of a union push with help from the Retail, Wholesale and Department Store Union.

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