Officers shut down their post in the western county of Nandi to go and watch Barcelona beat Manchester United on Tuesday night.
While they were distracted by the game on screens at a nearby shopping mall, burglars broke into the post at Kamorwon.
The officers returned at 1am local time to find three assault rifles had been taken from a steel box in the commander’s house, which doubled as the armoury.
Nandi County Commissioner Samuel Kimiti confirmed the theft of the G3 weapons and 60 bullets on Wednesday.
He said the officers were being interrogated as part of the investigation.
“All the officers left the post and went to watch UEFA football match at the nearby trading centre and on returning to the post they noticed the room of the in-charge which is also used as an armoury in which the steel box is kept was broken,” read the police report.
“Search is being conducted for recovery of the stolen firearms. Other officers are being mobilised to swing into action.”
Two magazines containing 37 bullets were left behind by the thieves.