A part of New York's iconic Brooklyn Bridge collapsed injuring five members of a family who were taking shelter during a thunderstorm.

Authorities said a section of a decorative facade about 25 feet (7.6 meters) wide fell off inside an underpass of the bride at about 7.30 pm local time.

Jerome Dilligard, 52, told NY Daily News that he and his family had taken shelter under the bridge from the torrential rain when his wife noticed water seeping out from between the granite stones.

Dilligard said he rushed to get their car but the facade collapsed as soon as he left.

His four-month-old baby, Kiarra Jackson was knocked to the ground and the rest of the family buried by debris.

"They were right under the wall when it came down," he said. "My wife had to dig them all out. It's a miracle they got out with their lives."

Dilligard's wife Teresa and their children Kiarra, Kaylah, 8 and LaToya Jackson, 30, and her son Khmani, 10, suffered from minor injuries and were traded at the Bellevue Hospital in Manhattan.

Fire and rescue units arrived at the scene and inspectors with the Department of Buildings were investigation the incident.

New York City Fire Department (NYFD) said that the collapse didn't affect retaining walls and the structural integrity of the bridge.

The collapse came as a severe thunderstorm was lashing the city prompting authorities to issue flash flood warnings in some areas.