Militants from the Islamic militant group al-Shabab have massacred at least 36 non-Muslim workers at a quarry in northern Kenya.

The militants are believed to have crossed from neighbouring Somalia to attack the civilians, which the group claims to be one of a “series of attacks planned and executed by the Mujahideen to serve as a response to Kenya’s occupation of Muslim lands”.

Al-Shebab separated the Muslims from the non-Muslims at the quarry at Koromei, near Mandera, at around 01:00 local time (04:00 GMT) after ambushing them in their tents and executed them by beheading or gunshot.

The Kenyan Red Cross (KRCS) has said that it is working with the Government in airlifting the deceased bodies from the scene to Nairobi and proving support to the bereaved families.

The militants are reported to have been caught by security officials as they slept in their tents at a quarry at Kormey, 15km from where the massacre took place.

The attack comes less than two weeks after al-Shabab militants killed 28 others in the same town, and there is growing concern about security threat from the militant group in towns near to the Somali border.

Kenyan President Uhuru Kenyatta has replaced his interior minister and police chief following the massacre.