Fortune magazine reports that Walmart had closed down six of its stores where workers were agitating for better pay.

According to the giant chain, the stores needed plumbing repairs. The workers thought the move was retaliation for their activism for higher pay.

Walmart is owned by the Walton Family, each member a billionaire. The Walton Family Foundation is the biggest funder of vouchers and charters and organizations that advocate for them, in the nation.

The retail giant laid off 2,200 workers last week after temporarily closing five stores for plumbing repairs. Workers aren’t buying that rationale.

Wal-Mart workers are fighting back against the retailer’s decision last week to close five stores in four states for what the company says are plumbing repairs.

Workers at the company’s Pico Rivera, Calif. store who are associated with OUR Walmart, a group that advocates for better pay, say the closings are “retaliatory” in nature. They filed a charge with the National Labor Relations Board on Monday, claiming that the termination of more than 500 employees at the Pico Rivera Walmart constituted an unfair labor practice.

Last week, the retail giant, which employs 1.3 million workers in the United States, temporarily closed five stores—two in Texas and one each in California, Florida, and Oklahoma—for six months of plumbing repairs. The stores closed at 7 p.m. on April 13, which gave workers just a few hours notice that they were losing their jobs. The company provided two months of paid leave for both full-time and part-time workers. Employees could try to transfer to a different Walmart location during that time. Full-time workers who fail to find another Walmart job are eligible for severance starting June 19, but part-time workers aren’t entitled to that benefit….

The United Food and Commercial Workers International Union, which backs OUR Walmart, is listed as the filing party on the NLRB complaint, which claims that Wal-Mart targeted the Pico Rivera store because it has been “the center of concerted action by [workers] to improve wages and working conditions for all Walmart [workers] around the country.” The Pico Rivera store was the site of OUR Walmart’s first strike in 2012; workers at that location have participated in strikes and civil disobedience ever since.

Good grief, those workers might even want a union! Can’t have that!

*the original title had a Freudian slip, saying “schools” intend of “stores”