GLENDORA, Calif. (AP) - Five firefighters suffered minor injuries battling a blaze in a forest near Los Angeles that scuttled holiday hiking and camping plans for thousands.

Four crew members were treated for heat problems and one for a twisted ankle. No one had had to be hospitalized.

Fire managers on Tuesday increased the containment of the wildfire in the Angeles National Forest to 15 percent but say it will still take a week to get it completely surrounded.

The cause of the fire that started Sunday afternoon in the San Gabriel Mountains has not been determined.

No structures have burned. Firefighters say the burned acreage did not increase overnight and is still at 3,600 acres, or about 5 1/2 square miles.

Slopes up to 80 percent and heat are extending firefighting efforts.

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