U.S. Rep. Chellie Pingree, D-Maine, is calling for an investigation into why a national restaurant chain closed its Augusta outlet weeks after restaurant workers filed their intent to unionize.

Chipotle Mexican Grill workers hug in June after Brandi McNease, far right, dropped off a letter about starting a union at the restaurant in the Marketplace at Augusta. Joe Phelan/Kennebec Journal

In a statement Thursday, Pingree urged the National Labor Relations Board to investigate Chipotle Mexican Grill, an American chain of casual dining restaurants with stores in the United Kingdom, Germany and France.

“The timing of Chipotle’s store closure in my district is more than alarming, it raises serious concerns of illegal union-busting,” Pingree said. “My constituents at the Augusta store followed the rules and were well within their rights to organize the first unionized Chipotle in the country.

“The NLRB should immediately investigate why Chipotle – a Fortune 500 company – would turn around and shutter the first store to propose giving workers a voice. If this nationwide, multi-billion-dollar chain is found to have retaliated against workers in the process of unionizing, it must be held to account,” Pingree added.

The Chipotle Mexican Grill at the Marketplace at Augusta closed permanently Tuesday with company officials saying the decision was made because Chipotle had been unable to adequately staff the business. After learning about the closure, workers rallied outside the restaurant claiming the closure was “union busting 101.”

Some Maine legislative leaders also reacted Thursday to the closure and allegations it was connected to a union-busting effort by the multi-national corporation. The workers at the Augusta Chipotle filed a petition for a union election in late June. If they had been successful, Augusta would have become the first unionized store in the Newport Beach, California-based chain.

“The decision to close the Augusta Chipotle, the first store in the country where workers filed for a union election, is a blatant union-busting practice. This move shows Chipotle is trying to instill fear and using the Maine store as an example,” state House Speaker Ryan Fecteau, D-Biddeford, said in a statement. “It is disturbing and shameful that the company would shutter a store where workers are fighting to improve conditions and service.”

“The rest of the country is watching as Chipotle retaliates against its own employees and engages in what appear to be unfair labor practices,” said state Rep. Rachel Talbot Ross, D-Portland, assistant majority leader. “We are rooting for them and will continue to stand in strong solidarity with those fighting for dignity, safety and an equal opportunity in the workplace.”