A section of a stone facade inside a Brooklyn Bridge underpass collapsed late on Wednesday evening, injuring five people, a New York City fire official said.

The roughly 7.6-metre section of stonework toppled before 8 p.m., New York City Fire Department spokesman Jim Long said.

"There is nothing structurally wrong with the bridge," Long said, adding that the people who were injured were not hit with the heavier chunks of falling debris.

The cause was being investigated.