Los Angeles ? A growing wildfire sending massive billows of smoke into the sky north of Los Angeles nearly tripled in size Saturday, injuring three residents, destroying at least three homes, knocking out power to many more and spurring evacuations in a number of mountain communities.

Mandatory evacuations were extended Saturday into neighborhoods in the canyons on the northwestern edge of Altadena, Glendale, Pasadena, La Crescenta and Big Tujunga Canyon, Forest Service spokesman Bruce Quintelier said.

The flames crept lower down the slopes of the San Gabriel Mountains despite winds blowing predominantly in the other direction, threatening more than 2,000 homes in the La Canada Flintridge area. Officials estimated that 1,000 homes had been evacuated.

At least three homes deep in the Angeles National Forest were destroyed, and firefighters were searching for others, Dietrich said.