Kenya bus attack by al-Shabaab militants
A view shows the scene where attackers earlier ambushed a Nairobi-bound bus outside Mandera town, near Kenya's border with Somalia and EthiopiaReuters

At least 36 quarry workers have been killed in a fresh attack suspected to have been carried out by Somali al-Shabaab Islamists in North Kenya.

The attack took place in Koromei, a 15-minute drive from Mandera, where 28 people were killed on 22 November after a bus was ambushed.

According to residents in the area, the gunmen attackers separated Muslims from non-Muslims and shot the Christians dead.

A person had earlier been killed in a bar popular with non-Muslims in a neighbouring district.

Several others workers are missing following the attack though the exact number is unclear. Local reports suggest about 20 gunmen were involved in the ambush.

Some of them were decapitated during the attack, which took place between midnight and 01:00 am this morning.

Just like the previous attack, only non-Muslims were said to have been targeted.

"We have the reports of quarry workers being killed but we will give you more and detailed information," police chief David Kimaiyo said.

The Somali militant group al-Shabaab is suspected to be behind the assault, though it is yet to officially claim responsibility.