Authorities issued evacuation orders and warnings to nearby areas early Friday morning as a wildfire in the Otay Wilderness Area exploded to 4,250 acres in rugged terrain overnight. Crews were able to get 10% of it contained.

A fast-moving wildfire erupted several miles north of the U.S.-Mexico border in the San Diego area, blackening thousands of open acres as ground and airborne crews worked Friday to quell the flames amid arid and blustery Santa Ana conditions.

Border 2 Fire initially started 2:31 p.m. Jan. 23 in San Diego County. After being active for 20 hours, it has burned 5,389.4 acres, an increase of 1,139 acres since the last update. A fire crew of 692 effectively contained 10% of the fire by Friday noon. The blaze's cause remains under investigation.