ELY  (AP) - A fire continues to slowly grow in the Boundary Waters Canoe Area Wilderness northwest of Ely.

A spokeswoman for the Superior National Forest said Tuesday the fire is now estimated to have burned across about 40 acres. That's up from an estimated 30 acres Monday.

Forest Service personnel are on the ground cutting trees and digging a line around the fire.

Helicopters and airplanes also may be used to drop water on the fire.

A 10-person ground crew from Michigan is expected to be flown in Tuesday to relieve local crews.

It's unclear if the fire started from lightning or a campfire.

The BWCAW remains open for canoe travel and camping, but camping is not recommended on nearby Otter Lake because of smoke.

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