A man seeking "a private audience" with Donald Trump spent hours scaling the glass facade of Trump Tower using large suction cups before police officers grabbed him and hauled him to safety through an open window.

Police have identified the climber as a 20-year-old Virginia man and say he's being evaluated at a hospital.

He wore a backpack and used a harness and rope stirrups to fasten himself to the side of the 68-story Manhattan skyscraper on Wednesday. He climbed as high as the 21st floor before officers grabbed him.

The tower is headquarters to Donald Trump's Republican presidential campaign and his business empire. Trump also lives there, although he was away Wednesday.