The NFL has asked a federal judge to dismiss lawsuits filed by thousands of former players who say the league hid information suggesting a link between concussions and brain injuries.

Some of the players say they're suffering from dementia and Alzheimer's disease, while others fear such problems and seek medical monitoring.

The league filed court papers Thursday asking a judge in Philadelphia to dismiss about 140 suits that she oversees.

The NFL says the issue is covered by the collective bargaining agreement, and that two other courts have agreed they should not get involved.

U.S. District Judge Anita Brody has been assigned to handle pretrial issues for suits that involve more than 3,300 players.

It's not clear if she'll hear arguments on the motion to dismiss the case.

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