Brush fire burns 50 acres in Pomona

POMONA, Calif. (KABC) -- Firefighters battled a brush fire that burned 50 acres in Pomona on Monday, L.A. County fire officials said.

The fire prompted evacuations as it moved uphill after originating along North Fairplex Drive near the 10 Freeway shortly before 3 p.m., according to L.A. County fire officials.

Using a water-dropping helicopter and a dozen engines, firefighters were able to slow its forward progress around 3:45 p.m. and reached 70 percent containment around 9 p.m.

No structures were threatened, per L.A. County fire officials.

The cause of the fire was not immediately known.

The City News Service contributed to this report.