Wildfires burning in Los Angeles County have left five people dead and burned thousands of structures to the ground this week, becoming some of the most destructive the area has seen in decades.

Firefighters battled early Thursday to control a series of major fires in the Los Angeles area that have killed five people, ravaged communities from the Pacific Coast to Pasadena and sent thousands of people frantically fleeing their homes.

The failure of the Los Angeles Sheriff’s Department’s computer-aided dispatch system in its vehicles had left deputies to resort to old methods as they responded to calls.