All nine people aboard a business jet were killed after it crashed into a South Florida neighbourhood on Sunday, US transportation secretary Sean Duffy said.The Learjet 60, which departed from Austin, Texas, was headed to the Bahamas when it nose-dived into the neighbourhood and burst into flames. The crash created a large fiery crater in the pavement near a busy roadway, news agency AP reported.The aircraft appeared to narrowly miss nearby homes before crashing, according to initial reports.Duffy said the Federal Aviation Administration was sending a team to assist the National Transportation Safety Board (NTSB) in investigating the cause of the crash.The circumstances leading to the crash and the identities of those killed were not immediately clear.