BOULDER, Colo. (AP) -- A fast-moving wildfire has erupted in northern Colorado, destroying at least one home and threatening other as residents in the Boulder foothills about 35 miles away return to their homes after one of the most destructive fires in state history.

Four helicopters and four air tankers are helping about 80 firefighters trying to contain the blaze in Loveland, Colo. So fire, that fire has burned about 600 acres, or just under a square mile. The new wildfire pulled some of the resources trying to finish containment at the fire outside Boulder.

The Boulder fire destroyed 166 homes and was at 73 percent containment Sunday.

The Denver Post reports that investigators at the Boulder fire were looking at the possibility that the blaze was sparked by a resident's fire pit.

PHOTO GALLERY

MAP OF AFFECTED AREAS:

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