ATLANTA — Some former NFL players say in a new federal lawsuit that brain injuries have left them struggling with medical problems years after their playing days ended.

Jamal Lewis, Dorsey Levens, Fulton Kuykendall and Ryan Stewart filed the lawsuit against the National Football League and NFL Properties LLC this week in U.S. District Court in Atlanta.

The players maintain the NFL knew as early as the 1920s of the potential for concussions to harm its players.

The court documents say the league concealed the dangers from coaches, trainers, players and the public until June 2010, when it publicly acknowledged the health threats and warned players and teams.

NFL representatives did not immediately return phone calls from The Associated Press.

All four ex-players live in metro Atlanta.