Kenyan officials say at least 10 police officers are dead after their vehicle struck an improvised explosive device near the Somali border in a suspected extremist attack.

The officials, who spoke on condition of anonymity because they were not authorized to share the information, said those killed Saturday in Wajir County were among 13 officers who were pursuing extremists who had kidnapped police reservists.

Police on Friday said an unknown number of gunmen stormed Konton center in Wajir East and kidnapped three reservists.

There was no claim of responsibility for the latest attack. The Somalia-based al-Shabab extremist group often targets Kenyan security forces, vowing retribution after Kenya deployed troops to Somalia in 2011 to combat the extremists.