Baltimore bridge collapse: Expert view on what happened

In the early hours of Tuesday morning, a cargo ship leaving the US city of Baltimore catastrophically struck a major bridge. The entire middle section of the 1.6-mile-long Francis Scott Key Bridge collapsed into the Patapsco River. <br /> <br />The ship lost power as it left the port, but the crew had enough time to make a mayday call so officials on the bridge were able to shut it to most traffic. Two people were rescued from the water but several people are still missing. <br /> <br />There are now questions about how such a large vessel lost control and how the huge structure of the bridge crumbled so quickly.  <br /> <br />On today's edition of the Sky News Daily, Leah Boleto speaks to our US Correspondent Martha Kelner in Baltimore and our Science Correspondent Thomas More. Plus, Ben Schafer, a structural engineer at Baltimore's Johns Hopkins University explains why the bridge fell so quickly.   <br /><br />Senior producer: Annie Joyce <br />Assistant producer: Iona Brunker  <br />Editor: Wendy Parker