Investigators announced Monday five fires ignited along a four-mile stretch of Interstate 25 last week near Fort Collins were sparked accidentally by a vehicle.

According to Poudre Fire Authority, the fires were likely started from a chain dragging from a vehicle on the road.

The biggest fire burned about an acre along the highway. The fires drew a multi-agency response but were all put out within an hour.

On Oct. 17, a cigarette sparked a 4-acre fire in the area east of I-25. Dry and windy conditions threatened to push the fire further before firefighters contained it.

PFA firefighters also quickly contained a five-acre fire Wednesday afternoon west of Overland Trail and near the Christman Field airstrip. The cause of the fire has not yet been determined, but the fire moved through dry grass and other fuels. It burned land owned by Colorado State University and privately-owned land.

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