The suspects attempted to force their way into the British army camp in Laikipia County in central Kenya on Sunday. Their photos were circulated after being captured on closed-circuit television camera, Laikipia County Criminal Investigations Officer Peter Muinde said.

"Later in the day (Sunday) as the chief and security officers were following up leads, they found them (the suspects) near Nanyuki police station where they arrested them," Muinde said.

Investigations are ongoing into the incident which came hours after Somalia-based extremist group al-Shabab stormed a military airstrip in Manda Bay along Kenya's eastern coast.

The US Africa Command, responsible for military relations with 53 African nations, said a US service member and two civilian contractors working for the US Defense Department were killed in the attack.

Al-Shabab claimed responsibility for the attack.