Thugs hacked three watchmen to death at Kivayea Secondary School in Matete sub-county, Lugari constituency, on Thursday morning.
The attackers whose number remains unknown injured another watchman while another escaped.
The bodies were found in different locations in the wee hours of the morning.
The injured watchman -Situma Shitikho, 45 - is admitted at the Webuye Sub-county Hospital in Bungoma county in critical condition.
The deceased were identified as Edward Wanyama, 40, Henry Khaoya, 55 and Evans Wanyonyi 56.
Luca Wanjala escaped.
The thugs stole a television set and a public address system from the staff room.
They also stole a laptop from one of the offices during the attack at 3am.
Matete Sub-County police commander Thomas Ototo confirmed the incident.
"The watchmen could have been hacked while asleep from where they had positioned themselves because there were no signs of d struggle," he said.
He said there was no attack attempted on the students. He said that police had launched investigations into the incident adding no arrest had been made so far.
The police boss urged the public to volunteer information that can lead to the arrest of the criminals.
The bodies of the deceased were moved to the Webuye Hospital mortuary in Bugonga Sub-county.
