Cal Fire crews battled a brush fire burning near the U.S-Mexico border east of the Otay Mesa Port of Entry overnight.
The 9-acre fire started at around 11 p.m. Monday in what Cal Fire called Tin Can Canyon near Otay Mountain.
Cal Fire spokesperson Issac Sanchez on Monday said the 5-acre fire was spreading at a moderate rate.
The rate of spread slowed Tuesday morning but was in a difficult area to access, Cal Fire San Diego tweeted.
By about 10 a.m. Tuesday, the fire was estimated to be 9 acres and crews had the blaze 75 percent contained.
The fire was not threatening any structures.
No other information was available.
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