The wildfire that has scorched 13 square miles and destroyed dozens of homes in the hills above this scenic coastal city was apparently sparked by a power tool being used to clear brush, investigators said Sunday.

Fire officials said someone, or possibly a group of people, was clearing vegetation on what appeared to be private land near the trail around the time the fire erupted Tuesday.

"Any time you use any power tool, there's always a possibility, especially if the conditions are right," said Joe Waterman, the overall fire commander from the California Department of Forestry and Fire Protection.