Several killed when foot bridge collapses at Florida university

Several killed when foot bridge collapses at Flori...

Several killed when foot bridge collapses at Florida university

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A pedestrian bridge spanning several lanes of traffic collapsed on Thursday at Florida International University in Miami-Dade County, trapping people and cars underneath the structure, with local media saying several people were killed.

Bad engineering?

Cost cutting with a catastrophic result?

Over-graded Chinese steel?

What is the cause of this collapse?