Authorities are investigating the cause of a plane crash near the French Valley Airport in Murrieta, California that killed six people. The National Transportation Safety Board (NTSB) and the Federal Aviation Administration (FAA) are conducting a joint investigation into the incident. The Cessna C550 business jet crashed in a field around 4:15 a.m., bursting into flames. The plane had been en route from Las Vegas to French Valley Airport when it crashed. Weather conditions at the time, including heavy fog, may have contributed to the accident. However, it is still too early to determine the exact cause of the crash. A spokesperson for the NTSB stated that they are in the evidence gathering phase and it would be premature to come to any conclusions. This is the second fatal crash near the airport in a week. The NTSB is expected to be on the scene for one to two days, and a preliminary report is expected in about 14 business days.