(AP) TUCSON, Ariz.

A wildfire burning in steep, rugged terrain in the Baboquivari (bab-oh-kee-VAR'-ee) Peak Wilderness Area of southern Arizona has grown to about 8 square miles, or 5,400 acres.

About 200 people and two helicopters are battling the Elk Horn fire, which began Thursday and is believed to be human-caused.

Arizona State Forestry Division spokeswoman Judy Wood says the fire is 8 percent contained and is expected to continue burning for the next several days.

She says fire crews are providing structure protection for the Los Delicious Ranch and in Brown Canyon.

Wood says burnout operations by fire crews during the next several days are expected to increase the amount of smoke visible from the blaze, which is burning 50 miles southwest of Tucson.

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