San Diego County officials identified four of the jet’s six occupants killed in the crash and ensuing fire. One was 42-year-old music agent and certified pilot David Shapiro, who owned the company to which the Cessna 550 Citation II was registered.

A National Transportation Safety Board investigator said both the runway lights and an automated weather-notification system at the destination airport were inoperable when the Cessna 550 plowed into the Murphy Canyon neighborhood at about 3:45 a.

Investigators are still trying to determine the cause of a San Diego plane crash that left at least three people dead and several others injured in the military housing neighborhood of Murphy Canyon on Thursday.