Crews Battle 'Sterling Fire' in Foothills Near San Bernardino

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A spokeswoman with the forest service says they do have a line around the fire, which means they've got a good handle on it and that there are no structures currently threatened.

The fire started around 6:30 yesterday evening and spread to 100 acres before midnight. One helicopter and 300 fire personnel have been aggressively attacking the blaze through the night.

Initially, 30 homes were threatened by the flames...but the blaze shifted, moving northeast into the foothills of the San Bernardino Mountains and away from residences.

Drones have been causing some real issue for firefighters.

Right Before nightfall aircraft were temporarily halted because a drone flew over the fire, which is considered restricted airspace. The pilot was not located. Sheriff's deputies spoke with another drone pilot, a teenager, but determined he was legally flying the unmanned aircraft.

This is the 2nd time... In a matter of days that aircrafts had to be grounded while fighting fires due to drones.

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