Investigators say a plane crash in San Diego that killed six people happened as the private plane approached an airport whose runway lights were out in heavy fog.

The pilot of the private jet that crashed early Thursday morning in Tierrasanta, killing all six people on board and injuring eight people on the ground, did not declare an emergency or call in any type of mechanical issue with the plane before it clipped a power line and slammed into a residential street, federal authorities said Friday.