The largest federal employee union filed a lawsuit on Thursday seeking to block President Donald Trump's administration from ending collective bargaining for nearly 50,000 Transportation Security Administration officers that staff checkpoints at U.

The largest federal employees union is suing the Homeland Security Department to stop the Trump administration from canceling its contract with T.S.A. workers.

The announcement comes a week after the US Department of Homeland Security (DHS) terminated the collective bargaining agreement.

The largest federal government employee union is alleging in a new lawsuit that the Trump administration violated its First Amendment rights and the "hallowed" sanctity of contracts by canceling a collective bargaining agreement covering Transportation Security Administration (TSA) airport security screeners.

A union representing Transportation Security Administration workers calls the Department of Homeland Security's decision to end the collective bargaining agreement with them an “unprovoked attack.”

The American Federation of Government Employees accused the Trump administration of retaliating against the labor group over their efforts to block the mass firing of probationary workers across government.