Investigators are done with their work at the airport . The Asiana plane 's wreckage is still there for future examination . The NTSB is doing further work with first responders . The National Transportation Safety Board has wrapped up its on-scene work as part of its investigation of the Asiana Flight 214 crash at San Francisco airport , the agency said Monday . The May 6 crash of the Boeing 737 killed four people .
Investigators are done with their work at the airport . The Asiana plane 's wreckage is still there for future examination . The NTSB is doing further work with first responders . The May 6 crash of the Boeing 737 killed four people .