NEW YORK — The NFL players’ union says former San Francisco 49ers safety Eric Reid filed a grievance against the league, alleging that he remains unsigned as a result of collusion by owners.

Reid, a Pro Bowler in 2013, had joined former teammate Colin Kaepernick two seasons ago in kneeling during the national anthem to protest police brutality and racial inequality.

Kaepernick wasn’t signed for the 2017 season following his release in San Francisco. Reid continued the quarterback’s protests. The 26-year-old safety became a free agent this offseason when his rookie contract with the 49ers expired.

“Our union is aware that Eric Reid and his legal representatives filed a collusion claim, which will be heard through the arbitration process as spelled out in our collective bargaining agreement,” the NFL Players Association said in a statement Wednesday. “Our union supports Eric and we are considering other legal options to pursue.”

Kaepernick previously filed a collusion grievance that is in the discovery stage. He deposed several league owners and executives, including Commissioner Roger Goodell. Reid is using the same attorneys as Kaepernick.