What happens in this video ?

July 6th 2013 - San Francisco airport, CA, USA - The Boeing 777-200 operated by Asiana Airline took off from Seoul, South Korea, for a passenger flight to San Francisco, CA, USA. 291 passengers and 16 crewmembers were onboard. During landing, the plane touched down short of runway impacting the edge separating the runway from the San Francisco Bay, and crashed. 3 people were killed in the accident, 10 people were seriously injured, and 120 people were injured. The majority of survivors escaped without injuries.
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