A 4,200-acre wildfire that threatened hundreds of homes was 35 percent contained early Sunday, fire officials said.

Though an evacuation order was lifted for some residents of scenic Oak Creek Canyon on Saturday, the blaze still threatens homes in the canyon's southern end, where crews focused on finishing a protection line.

Overnight efforts to widen the lines protecting the homes went as planned, said David Eaker, a spokesman for the team fighting the fire.

Authorities said it will be about two days before the remaining evacuees can return home. Officials hope to have full containment by Wednesday, barring any weather disturbances that could push the flames.

"In my mind, we have crossed the threshold where we are on the offense, chasing it down," Mike Dondero, deputy incident commander for the fire, said late Saturday. "And we are gaining on it real fast."

The fire started June 18 north of Sedona as a transient's campfire and spread to steep terrain above the canyon. No homes have burned.

North of Sedona, officials reopened two roads in Grand Canyon National Park that were closed because of a 15,500-acre wildfire.

The fire raised questions early Saturday about whether visitors would be stranded in the park. As fire activity lessened, the road closures were lifted later in the day, said Bill Kight, fire information officer.

An unknown number of tourists were voluntarily escorted out of the Grand Canyon's North Rim. The North Rim, which is significantly more remote and less popular than the park's main South Rim entrance, remained open to visitors.

The blaze, which had not threatened any property, was allowed to burn since it was discovered June 8 in the Kaibab National Forest after a series of lightning strikes.

Elsewhere, a nearly 48,000-acre blaze in southwestern New Mexico's Gila National Forest was 23 percent contained Saturday. It had destroyed a cabin and was threatening about 80 other structures. It was started by a campfire, officials said.

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In Southern California, a 15,000-acre wildfire in Los Padres National Forest was 85 percent contained, and crews hoped to have it fully contained by late Sunday, officials said. The blaze 45 miles east of Santa Maria was started Monday by an electrical short circuit, and had destroyed two sheds and three oil company trailers.

Hundreds of firefighters in southern Colorado were battling a nearly 14,000-acre wildfire that was sparked by lightning a week ago. Residents of about 50 homes were allowed back into the area Sunday afternoon. Another fire in southern Colorado that started Friday forced the evacuation of 12 homes Saturday afternoon.

Wildfires have charred 3.2 million acres nationwide so far this year, well ahead of the average of just over 1 million acres by this time, the National Interagency Fire Center reported. Huge grass fires that swept Texas and Oklahoma this spring account for much of the increase.