The Lawrence school district says it investigated a report that two staff members at an elementary school apparently were exposed to carbon monoxide.

The district said in a news release Monday that two employees from Kennedy Elementary School reported they had tested positive for elevated carbon monoxide levels.

The Lawrence Journal-World reports district spokeswoman Julie Boyle said in a news release that workers discovered a natural gas water heater had not been venting properly because a vent was covered.

Boyle said the district was trying to determine how long the vent had been covered. The problem was fixed and the district tested the area during the weekend.

She said Lawrence Douglas County Fire Medical and Black Hills Energy completed an inspection at Kennedy Monday and found no carbon monoxide.

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