A search and rescue operation is underway in the United States after a cargo vessel slammed into the central support pillar of one of the largest bridges on America's eastern seaboard.
The bridge in Baltimore collapsed within seconds, with several motorists and other people swept into the icy river beneath it.
Early reports suggest the vessel suffered a catastrophic power failure moments before the accident.
Six people are still unaccounted for, after 2 were rescued from the river, one in a serious condition.
Washington Correspondent Simon Marks reports.