SAND SPRINGS, Oklahoma -
Clyde Boyd Middle School in Sand Springs was closed again Thursday after Monday's carbon monoxide leak.

The school district says repairs are still underway and gas service to the school hasn't been restored yet. Workers have installed carbon monoxide detectors and the district is re-evaluating its procedures.

The OSU Medical Center said they treated 12 kids for CO exposure Monday. More than 50 additional students went to other area hospitals for treatment.

Oklahoma Poison Control said they dealt with 18 patients through phone consultations in addition to the calls they received from hospitals about carbon monoxide poisoning Monday evening.

The district said parents should call the central office on questions about medical expenses.