Lukenya Assistant County Commissioner Elizabeth Karitu was on Saturday night arrested after losing the keys to the Machakos County national examinations container.
Ms Karitu claimed to have lost the keys after thieves broke into her car in Nairobi and took her handbag.
In a statement, County Commissioner Elizabeth Maina said she was arrested when she went to report the incidence at Parklands Police Station .
She was detained there.
Ms Maina said Ms Karitu had gone to Avenue Hospital in Nairobi and that when she returned she found her car had been broken into and her handbag stolen.
"She has consequently been interdicted and security has been beefed up in the container amid efforts to replace the padlock immediately," she said.
Ms Maina further said that arrangements to replace Ms Karitu had been finalised.
"Everything is under control. There is no cause for alarm," she said, adding they were working with the Kenya National Examinations Council.
Standard Eight candidates will write the Kenya Certificate of Primary Education exams from October 28 to 31.
Form Four candidates will begin their Kenya Certificate of Secondary Education exams on November 4 and finish on November 27.