LAKESIDE, Calif. — Officials say a forest fire that forced the evacuation of several rural Southern California campgrounds has exploded in size to nearly 12 square miles.

U.S. Forest Service officials say the blaze in the San Bernardino Mountains has grown significantly Thursday despite an attack by crews using water-dropping aircraft. Just hours earlier the size of the fire was estimated at about 2 square miles.

Flames are churning through 30-foot-high trees, sending up a huge plume of smoke visible for miles. The fire in the San Gorgonio Wilderness area is just 5 percent contained.

Nearly 200 campers, most of them children, were evacuated from several wilderness sites after the fire was reported Wednesday afternoon about 90 miles east of Los Angeles.

First Published June 18, 2015, 7:22 p.m.