UPDATE: The Deschutes County Sheriff's Office issued a Level 1 Pre-Evacuation notice Monday for Black Butte Ranch and other areas between highways 242 and 20 and west of Cold Springs Cutoff Road (FS 1012).

While the Milli Fire continues to be 20 percent contained Sunday, police attributed the new evacuation alert to “increased fire activities."

A community meeting about progress fighting the fire will be held Tuesday at Sisters High School at 6 p.m.

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SISTERS, Ore. (AP) - About 600 residents are under evacuation orders in a prime eclipse-viewing location in Oregon threatened by the "Milli Wildfire" that has closed access to part of a wilderness area and a regional highway.

Fire officials said Saturday another 1,000 residents near the tourist town of Sisters have been told to be ready to leave if necessary.

The fire had reached more than 9,000 acres Sunday — doubling in size since last Thursday — and was at about 20 percent contained. But officials said they made enough progress fighting the fire that it's unlikely they will order more evacuations.

Check the latest fire updates from the US Forest Service

Some campsites and recreational areas are also shut down due to the 12-square-mile wildfire in the Deschutes National Forest that jumped fire lines Friday.

Officials say the blaze is producing heavy smoke while burning in forests at higher elevations and in sagebrush at lower areas.

The fire started late last week. Its cause is under investigation.

Oregon crews were also busy fighting the Nena Springs wildfire on the Warm Springs reservation.

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