WEST FARGO, N.D. (AP) — A faulty furnace is cited as the cause of a carbon monoxide leak at a West Fargo business.

Authorities were called to a Subway restaurant Monday and determined an ill employee was suffering from exposure to high levels of the potentially deadly gas. The worker was taken to a hospital and is now recovering at home.

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Authorities detected lower levels of carbon monoxide at a preschool in the same building and evacuated it until crews could ventilate the building.

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No one other than the Subway worker reported any ill effects.

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