The Milepost 97 fire charring southern Oregon grew overnight and has now engulfed more than 11,000 acres.

Additional crews arrived Saturday to begin battling the largest blaze in the Pacific Northwest during what has otherwise been a quiet fire season.

Crews are fighting the fire from all directions, with special attention along Interstate 5.

“They don’t want anything crossing the freeway onto the east side,” Jim Gersbach, a spokesman for Oregon Department of Forestry assigned to the fire, said Sunday morning.

The fire is burning near Canyonville, a small city between Roseburg and Grants Pass, about 100 miles north of the California border. Southbound traffic on I-5 is limited to one lane near Canyonville, and fire crews have placed equipment and vehicles along the shoulder of the freeway.

Anyone traveling through the area should expect slowing. Freeway updates are available at www.tripcheck.com.

“There’s a lot of traffic associated with the fire activity,” Gersbach said. “We want people to be getting through there as safely as possible.”

The Milepost 97 fire grew by about 2,000 acres late Saturday and early Sunday, Gersbach said. As of 6 a.m., it had reached 11,009 acres.

Before the surge, the fire had been at a 5 percent containment. Gersbach said he didn’t have an updated number Sunday morning.

Authorities believe the fire sparked Wednesday because of an illegal campfire. More than 900 personnel have been assigned to the blaze, with firefighting efforts now coming from air and ground.

Level 2 orders are in place for some areas, instructing residents to be prepared to evacuate. Officials will hold a community meeting at 7 p.m. Sunday at Glendale High School.

-- Brad Schmidt

bschmidt@oregonian.com

503-294-7628

@_brad_schmidt