<a href="http://losangeles.cbslocal.com/photo-galleries/2011/08/22/brush-fire-burns-in-cajon-pass/" target="_blank">» PHOTOS: Crews Battle Massive Wildfire In Cajon Pass</a>

CAJON PASS (CBS) — A wildfire has scorched more than 300 acres and a mobile home in the Cajon Pass Monday afternoon.

The wildfire began on Interstate-15 in the Cajon Pass between Kenwood and Cleghorn at approximately 1:00 p.m., according to San Bernardino National Forest spokesman John Miller. Officials say two structures have also burned.

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Crews have contained about 40 percent of the brush fire.

Caltrans says only three of five northbound lanes of I-15 are open and there is a heavy backup. The southbound side is fully open but is also experiencing spectator delays.

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Authorities said no one has been injured. Two residents at the Matthews Ranch were asked to evacuate but refused.

No other evacuations have been ordered.

Approximately 40-50 miles away, another brush fire was burning in the city of Perris and fast approaching homes. About a dozen residents have been ordered to evacuate.

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The blaze has consumed at least 100 acres.

» PHOTOS: Crews Battle Massive Wildfire In Cajon Pass