PLACER COUNTY (CBS13) — Investigators have found that this year’s River Fire in Placer County was human-caused.

Cal Fire said on Friday that investigators have determined the fire started on Aug. 4 in the overnight camping area of the Bear River Campground near Colfax.

The fire went on to burn 2,619 acres. A total of 142 structures in Placer and Nevada counties were destroyed, officials say. Four people were injured in the fire, including two fighters and two civilians.

Exactly what started the fire has still not been detailed. Cal Fire says their investigation is still ongoing.