A group of armed men thought to be from the Islamic terrorist group Al-Shabaab ambushed a bus travelling from Nairobi to Mandera on 6th December, according to International Christian Concern (ICC).
Militants reportedly separated the 56 passengers on board into groups of local Muslims and non-local Christians.
The victims were then executed for failing to recite the Islamic creed, known as the Shahada - which declares belief in Allah and Muhammad as his prophet.
Confirming the incident to ICC, a Kenyan police officer said: "A passenger bus belonging to Medina Bus Company, traveling between Wajir and Mandera was attacked by a criminal gang at around 5:30pm. The attack happened at Maadathe area, five kilometers to Kotulo. Lives are believed to have been lost."
Mandera's governor has condemned the terror attack as "cowardly" and "disturbing" while the office of Kenyan President Uhuru Kenyatta released a statement warning action will be taken to bring the assailants to justice.
It read: "The government will not relent in its ruthless crackdown on criminal elements including suspected terrorists in its solemn duty to safeguard the lives and property of Kenyans.
"The head of state further sends a strong warning and reminder to misguided elements operating within and outside of our national borders and whose actions harm innocent Kenyans that no effort will be spared in neutralizing the threat."
A similar attack was orchestrated by Al-Shabaab militants in 2018, when a bus on route to Garissa was targeted and two Christians were killed for allegedly refusing to recite the Lord's Prayer.
Nathan Johnson, ICC's Regional Manager for Africa said: "We pray for the families of the deceased and for peace to come to a region that has seen increased violence toward Christians who are just trying to survive.
"We hope that the government will take effective action to stop the senseless killing of so many Christians in Kenya at the hands of Islamic extremists like al-Shabaab. We praise God as the refuge and strong tower that He is for our persecuted brothers and sisters in Christ who continue to endure so much."
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