Narok County Commissioner George Natembeya has announced plans to subject girls to pregnancy tests before they return to school next year.
This is part of efforts to minimise or end cases of teenage pregnancies in the region.
The administrator, who spoke in Nairegie Enkare in Narok East on Tuesday, said it will also be established whether the girls underwent female genital mutilation during the December holidays.
The rite of passage is illegal in Kenya but it is rampant in counties including Narok.
A tough-talking Natembeya said the parents of children subjected to FGM will be arrested and prosecuted.
He further that said that girls found to have undergone the cut will be forced to record statements with police while those who get pregnant will reveal the identities of the men responsible.
"It will not be business as usual. I hereby direct school heads to have girls in secondary and upper primary schools undergo the tests at local health facilities once the institutions reopen," said Mr Natembeya.
The administrator linked rising cases of teenage pregnancy cases to FGM, saying girls who undergo the cut feel mature enough to have sex.
Regarding the rite of passage, he said a special police unit has been formed and tasked with investigating the cases during the holidays. The team is called the Anti-FGM Unit
School heads were also asked to immediately report cases of students dropping out for action to be taken.
The Demographic Health Survey (DHS) report found that Narok was leading nationally in teenage pregnancies, the rate being 40 percent.
The commissioner sternly warned chiefs and their assistants against abetting the vices, saying those found culpable will be fired.
"I understand there is a section of chiefs who are bribed with cows to allow FGM, teenage pregnancies and early marriages to take place," he said.
"Be on the lookout because we are coming for you. We shall fire you, arrest you and prosecute you."
On Monday, Director of Public Prosecution Noordin Haji has ordered police to investigate the many cases of teenage pregnancy and early marriage in Kilifi County and other parts of the country.
Mr Haji asked the Directorate of Criminal Investigations to send the files to his office for action, once the investigation is completed.