The incident occurred two days after 13 people died in Arabia, Mandera county, in a similar manner.
Last November, ISIS-linked militants beheaded over 50 people, including women and children.
Attacks by Al-Shabaab in Kenya most often involve the killing of Christians in small villages or who are riding on buses.
Al-Shabaab is a jihadist militant organisation whose primary aim is to create an Islamic Statate in Somalia.
At least eleven people were killed last week in Mogadishu, the capital of Somalia, in a suicide bombing.
It is vital that the international community push back as IS fights to spread its radically harmful ideology across Africa.
Fortunately, they were not able to identify any non-local passangers.
The attack on the Manda Bay Base cost the lives of three Americans, a soldier and two contractors.