DURANGO, Colo. (AP) – A wildfire burning south of Durango has grown to an estimated 500 acres and is headed toward Lake Nighthorse.

The fire was burning in pinon and juniper on Southern Ute Indian Reservation land Sunday.

No evacuations have been ordered, but fire information spokeswoman Ann Bond of the U.S. Forest Service says 146 residents received pre-evacuation notices saying that they may have to leave if conditions change.

Fire officials believe the fire may have ignited from a lightning strike Friday or Saturday that smoldered into Sunday.

A gas well pad threatened earlier by the fire has been shut down.

Crews are fighting the flames from the ground and from above.

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