WASHINGTON – A DC main transit hub is the White House's next stop on its mission to take control of the nation's capital.

Transportation Secretary Sean Duffy said Aug. 27 his agency will put Washington Union Station "back under" federal authority as part of President Donald Trump's campaign to reduce crime and clean up the city.

The move is yet another expansion of the president's power over DC, which has long ruled itself.

Here's what to know about the federal takeover of Union Station:

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