The Burlington-Bristol Bridge was shut down Tuesday morning after a crash in the middle of the span. It has since been reopened.
Officials say garbage and debris on the sidewalk, and a couple of cars were on fire at the location before a large explosion occurred.
Video from the scene shows a 2016 Toyota Camry burning just feet from nearby homes. Chuck Fischer said he heard a loud noise before seeing the fire.
Authorities did not report any injuries and are still looking into what caused the fire.
The Picketts came upon the crash while driving back to campus after a family dinner in New York City's Times Square.
A house fire spread to cars Tuesday morning in Chalfont, Bucks County.