Mitchell spent seven years in the military before leaving to pursue a civilian career.
News helicopter footage showed dozens of firefighters scouring the debris, with a group appearing to use a saw to cut through the wreckage.
The 990-foot ship set a speed record on its first voyage in 1952. (BAY NEWS 9 (SPECTRUM NEWS))
The collapse happened in an area where construction had been occurring. (WABC)
The collapse happened in an area where construction had been occurring. (WABC)