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Former UFC fighter Leslie Smith has filed a complaint against the promotion after she was released from her contract last month.

Lucas Middlebrook, Smith's attorney, told ESPN's Brett Okamoto the complaint was filed with the National Labor Relations Board.

Smith set up a GoFundMe page to help with her legal fees as she continues to fight for the rights of professional fighters to unionize, writing:

"I have been one of few UFC fighters to publicly speak in favor of a fighter's union. I also recently launched Project Spearhead, an organization that is currently collecting authorization cards from UFC fighters to file with the National Labor Relations Board. I was the ninth ranked UFC Women's Bantanweight in the world and had won three of my last four fights, but the UFC's actions resulted in me being removed as a fighter in the UFC. It is my opinion that I was removed from the UFC in direct retaliation for exercising my rights to organize a union."

Smith was originally scheduled to fight Aspen Ladd in a bantamweight bout at UFC Fight Night 128 on April 21. Ladd missed the 136-pound weight limit by 1.8 pounds, and Smith turned down a catchweight bout on the show.

After UFC cut Smith when she declined to fight Ladd at the higher weight, she told Ariel Helwani on The MMA Hour podcast on Sirius XM's The Luke Thomas Show that what the company did "was illegal."

"Because they have created a situation where it encourages a climate of fear where the other people in the UFC on the roster are going to be fearful of publicly organizing and standing up for their rights,” Smith said.

In 18 career fights, Smith owns a 10-7-1 record. She went 4-3 since debuting in UFC in April 2014, with back-to-back victories in each of her last two bouts.