Tensions are high in Kapkosum village, Mochongoi, Baringo South after suspected robbers stormed the area and suspended KCPE exams at two schools.
Trade was also suspended during the morning round. Police said security was restored.
KCPE exams began around Monday.
Baringo County has been harassing candidates even as the national examinations start across the country.
Recently, attacks have increased in the area to the point where thugs target educational institutions.
A similar attack on Tot High School students and teachers on their way to school after a field trip resulted in the death of a school bus driver last month.
The robbers stormed one of the three buses carrying students and opened fire on people in the car, including teachers.
Thirteen people were injured in the attack