Somalia's al Shebab militants killed five police officers in a border region in northeastern Kenya on Monday, a regional official said.
There was no immediate statement from al Shebab, which has made a series of deadly incursions into nrighbouring Kenya, saying it will continue until Nairobi withdraws troops from an African Union force fighting the militants in Somalia.
"We condemn the attack by al Shebab at Dimu this morning, five police officers killed," Mandera County Governor Ali Roba said on his Twitter account.
Diplomats say Kenya's northeastern border with Somalia is a security weak spot, given the challenge of policing a long frontier, poor coordination between security services and a culture of corruption that allows those prepared to pay a bribe to pass unchallenged.
Al Shebab has targeted the Mandera region in the past.