Six teachers accused of defilement have been interdicted.
The county Teachers Service Commission director, Lois Murrey, said the teachers faced disciplinary action, including being taken to court and dismissal.
The official said a headteacher said to have made a pupil pregnant was one of two other teachers being investigated.
Ms Murrey warned teachers against having sexual relations with their students.
"We are taking this matter seriously. No teacher found abusing children will escape punishment," she said.
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She added: "According to our circulars and the code of conduct, teachers know that as professionals, they are also expected to protect children."
Elsewhere, the National Police Service has interdicted a police officer accused of defilement.
County Commissioner Maalim Mohammed said an inter-agency committee had been set up to deal with cases of defilement in the county.