NAMPA -- Fire crews are mopping up after a fire burned about 60 acres of brush and grass along I-84 in Nampa.

The fire sparked Thursday morning near the Northside Boulevard exit.

While no buildings were threatened, fire officials say heavy smoke forced Norco, a medical supply company, to shut down its ventilation system.

Crews had the blaze under control by noon.

The interstate was not closed down, but traffic was moving slowly in the area while crews fought the fire.

Investigators are looking into the cause of the fire.