The headteacher was arrested by the police in Mandera County. [iStockphoto]

A headteacher in Mandera County is behind bars after he was arrested over exam malpractice after three KCPE candidates were found with mobile phones in the examination room.

Confirming the arrest, Mandera CIO Benedict Kigen said the Tawakal Primary School headteacher was arrested after three phones were confiscated Tuesday at the school located in Mandera town.

"We have arrested Tawakal Primary headteacher and are interrogating him on how three of his candidates accessed the examination room while in possession of mobile phones," said Kigen.

According to Kigen, the three were fed with answers by accomplices in a neighbouring primary school.

"We suspect the answers were sent from a neighbouring exam centre. Once confirmed, we will also arrest the headteacher of that school too," said Kigen.

The CIO added that detectives are investigating another incident where a police officer was stoned at the same examination centre on Monday by unknown people.

The group allegedly stoned the officer after their attempts to sneak mobile phones into the school were thwarted.

"A police officer manning Tawakal examination centre was injured by unknown persons who rained stones into the school compound. We shall know the facts once we arrest other suspects and conclude our investigations," said Kigen.

7,771 Grade Six pupils are sitting for KPSEA tests, while 6,944 are doing the KCPE examinations in the County.