CHARLOTTE, N.C. – North Carolina first warned school districts across the state in May of 2011 that a specific model of school bus could potentially catch fire.

The NC Department of Instruction Transportation Division released a statement Friday saying the 2011 report warned of potential fires on CAT 3126 Freightliner Thomas Built buses, and ordered inspections and repairs if frayed wiring was discovered.

The statement says despite the 2011 warning, “DPI inspectors have still seen in some bus garages where they have not performed the repair to the valve cover wires…”

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The statement says a likely cause of fires is deterioration of plastic ties that hold back wiring harnesses from the heat of the engine manifold.

The statement reads, “The high exhaust manifold temperature allowed the alternator wire to fall on the manifold igniting the fire.”

Some parents of Charlotte-Mecklenburg students said they were surprised to hear that the state had known about the potential for fires since 2011.

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“I’m glad nobody got hurt but they should do something about it, cause I do have a 16-year old son that rides the school bus, so I hope nothing happens to him,” said Reginald Stitt.

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No one was injured in either of the CMS bus fires.

CMS says it has inspected all 259 buses of that same model and found “with no areas of concern found.”