UPDATE: [Evacuations Under Way As Crews Battle to Get 4S Ranch Fire Under Control]

Wind-stoked flames tore over open swaths of land near Del Norte High School Tuesday, blackening scores of acres and moving toward homes but causing no immediate structural damage.

The blaze erupted for unknown reasons about 10:40 a.m. amid hot, dry and gusty conditions off Camino San Bernardo, near Nighthawk Lane in Rancho Penasquitos, according to the San Diego Fire-Rescue Department.

Within less than two hours, the flames had scorched about 65 open acres, according to Cal Fire.

Crews from various agencies attacked the flames on the ground and aboard air tankers and water-dropping helicopters, a dispatcher said.

No evacuation orders were reported. Students at the high school were directed to remain in their classrooms as a precaution, as were pupils at nearby Del Sur and Stone Ranch elementary schools and Oak Valley middle school, said Jessica Wakefield, spokeswoman for Poway Unified School District.

“So we’re watching the fire, and we’re talking to the fire department to monitor the situation,” Wakefield said during the noon hour.

No serious air-quality issues were reported at any of the campuses, though the smoke was fairly thick at Del Sur Elementary, she said.

And in Campo, a brush fire of unknown origin engulfed two mobile homes while spreading amid unseasonably hot and dry weather near State Route 94 in the far southeastern reaches of San Diego County.

The blaze erupted near Shockey Truck Trail in Campo about 10:40 a.m., according to Cal Fire.

Ground and airborne crews were able to contain the burn area to about four acres, said Kendal Bortisser, a fire captain with the state agency.

No injuries were reported.

–City News Service