NEW YORK - A construction worker fell about 40 stories to his death Thursday at a midtown Manhattan skyscraper being built by the developer of the World Trade Center, authorities said Thursday.

The man, who was a rigger on a crew dismantling a crane, fell either from the crane or a 20-foot, moveable walkway linking it to the glass-walled skyscraper, said Deputy Fire Chief Anthony DeVita.

An impromptu memorial service was held inside the fenced construction lot where the worker landed, apparently killed instantly.

"This happens. We live with that," said stoic ironworker Luis Guzman, 44, who had been getting his tools together to head to the roof when the falling man crashed nearby.

Another ironworker, Jim Bradfield, 47, said it appeared the dead man had on a safety harness.

The accident happened at 600 W. 42nd St., where trade center developer Larry Silverstein is building two 60-story luxury apartment buildings. Construction began last fall on the development, called Silver Towers at River Place.

The Buildings Department halted work at both towers while the accident is investigated, but allowed the crane dismantling to continue to a safe point. DeVita said there were no structural problems with the crane or the tower.