LAKESIDE, Calif. - Automobile exhaust sparked a fast-moving wildfire that blackened about 400 open acres near Lake Jennings Tuesday, forcing evacuations of some back-country homes and prompting a full closure of a several-mile stretch of nearby Interstate 8, authorities reported.
The blaze erupted alongside the freeway near Olde Highway 80 in Flinn Springs shortly before 2 p.m., according to Cal Fire.
The flames soon were posing an immediate threat to five homes, the state agency reported.
Authorities directed those living along View Side Lane to clear out of the neighborhood while ground and airborne firefighters worked to corral the blaze.
County officials also issued an "evacuation advisory" for Peutz Valley and the northern end of Harbison Canyon in the Hunter Pass area, alerting residents of those locales that they might have to vacate if the blaze kept moving in their direction.
Temporary shelters for evacuees were established at Granite Hills High School on East Madison Avenue in El Cajon and at Joan MacQueen Middle School on Tavern Road in Alpine.
As the fire rapidly moved across hilly terrain to the southwest, the CHP shut down nearby Interstate 8 between Tavern and Lake Jennings Park roads. The closure resulted in hours of gridlock for miles to the east and west.
By 5 p.m., crews had halted the spread of the fire, allowing for the reopening of westbound and eventually eastbound lanes in the area.
Investigators determined that engine emissions from a passing vehicle ignited the blaze, which was 60 percent contained as of 4 p.m. Wednesday.