A suspected recruiter for Somalia's al Shabaab militant group being held in a west Kenyan police station shot dead at least four officers there on Thursday after snatching a weapon from a guard, an officer said.
The incident took place at Kapenguria police station in a region near the Ugandan border.
Al Shabaab has launched a series of attacks against Kenya in recent years, including using local recruits. The group says the attacks are aimed at driving Kenyan forces out of Somalia where they are part of an Africa force fighting al Shabaab.
The suspect was detained on Wednesday for interrogation and grabbed the weapon during a routine roll call early on Thursday morning, said the officer, who asked not to be named because he was not authorised to speak publicly.
"I can confirm that four police officers have been killed but they could be more," the officer told Reuters.
Kenyan television channel KTN said as many as six officers had died in the continuing stand-off. KTN and other Kenyan media said police reinforcements had been deployed.
"The suspect has locked himself inside one of the rooms and we are trying to get him out," the officer said. "We have surrounded the station."
A police spokesman and a regional official had no immediate comment.