A man visiting a law office at a Lower Manhattan office building Tuesday afternoon plunged five floors to his death from a staircase inside the building, according to police sources and the firm’s attorneys.

The man, who sources say is middle-aged and has a psychiatric history, jumped over the seventh-floor banister of the 25-story Trinity Building on Broadway near Pine Street around 12:50 p.m., where he had just visited the Gottlieb & Janey law firm.

He landed on the second floor, where he was pronounced dead, sources said.

“It was a tragedy at our office today,” one of the firm’s partners, Derrelle M Janey, said outside the building.

The man was not immediately identified by authorities.