A student facing murder charges is among 17,894 candidates sitting KCSE exams in Kitui county.
The 17-year-old is taking his papers at Kitui police stations cells as he awaits trial at the High Court.
He is accused of killing a boy during a football match earlier this year.
Area OCPD Muthuri Mwongera said: "County education director Susan Murerwa has provided an invigilator while I have provided a policeman to keep watch as the young man writes the exam."
He said the student will take practical exams at the nearby Kitui High School.
Some 615, 773 KCSE candidates have begun their 2017 examinations this morning.
The exams, which will end on November 29, are being administered at 9,350 centres countrywide.
KNEC chair George Magoha said they will be administered under strict guidelines meant to curb cheating.
Last week, primary school pupils sat KCPE examinations without any hitches.
According to the Kenya National Examinations Council, 1,002,922 million registered for the KCPE exam.
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