LARAMIE, Wyo. (AP) — Firefighters have reached 80 percent containment on a wildfire in the Medicine Bow National Forest west of Laramie.

The wildfire near Lake Owen in Medicine Bow National Forest had burned almost a square mile after it began on Monday.

Firefighters on Wednesday will concentrate on securing lines and looking for any spot fires that might have been ignited in the vicinity.

The Lake Owen campground and day use area remains closed.

There are about 140 firefighters on the scene supported by helicopters and heavy air tankers.

The cause of the fire is under investigation.