OKLAHOMA CITY - Classes have been canceled at Lee Elementary Tuesday, according to Oklahoma City Public Schools.
The school was evacuated after several staff and students became complained of nausea, dizziness and stinging eyes, the school district reported.
Oklahoma Natural Gas, the OKC Fire Department and EMSA responded to the school near S.W. 29th St. and Shields around 2:30 p.m. Monday.
Investigators found a carbon monoxide leak from a heating and air conditioning unit.
Crews said one classroom appears to have been the most impacted.
Ten people were treated, five adults and five children.
Six of those, three adults and three children, were taken to the hospital.
The unit will be replaced on Tuesday according to school officials and classes have been canceled.