MEXICO CITY (AP) — A final report on the helicopter crash last year that killed Mexican Interior Secretary Francisco Blake Mora and seven others says it was caused by pilot error.

Mexico's general director of airports and auxiliary services says investigators found no mechanical problems or evidence of an explosion.

Gilberto Lopez Meyer says the aircraft was flying through fog in near-zero visibility last November when the pilot changed course and the helicopter crashed into a mountainside south of Mexico City. Meyers said Friday there wouldn't have been an accident without the route change.

The interior secretary is the Mexican government's No. 2 official, and Blake Mora was the second interior secretary under President Felipe Calderon to die in an aircraft crash. Many Mexicans have found it hard to accept as an odd coincidence.