Al-Shabab militants on Friday killed two civilians in Garissa county in northeast Kenya, a government official said.

Northeastern regional commissioner Mohamed Birik confirmed the incident at Handaro saying a security operation was underway to try and arrest the militants who were believed to be still hiding in the forest.

Eyewitnesses said about seven armed al-Shabab militants had stopped a Garissa-bound commuter bus and ordered all non-locals (Christians) to alight from the bus which had left Holugho town at 9 am and was heading to Garissa when the incident happened at 11 am.

According to the witnesses, the militants who were all speaking in Swahili emerged from a nearby thicket where they intercepted the bus and ordered the driver to stop before entering in. They then ordered commuters to produce his identification card.

“The three non-locals were then separated from the rest of us (Muslims) before they were told to recite the Muslim Shahada and suratul Fatiha (Quran verses), the complete seven verses,” said the teacher who refused to be identified.

Only one of them managed to do all the verses. He was left while his two colleagues, a bus conductor identified only as Joshua and the other a casual laborer had their hands tied before being executed.

After committing the heinous act, the militants then escaped to unknown location.

“These militants were seven in number. They were all conversing in Swahili with one guy who resembled like a person from the Arab origin. They never seem to be in a hurry even as they went about carrying out the exercise,” said the teacher.

The incident comes after the regional government announced the recruitment of the Kenya police reservists in all the 60 locations across the region to enhance border patrols.

Islamist militants have staged a string of attacks in Kenya, including the April 2, 2015 massacre at Garissa University that left 148 students dead and a 2013 assault on Nairobi’s Westgate shopping mall that killed 67.

The East African nation continues to suffer several attacks as terrorists change tuck to beat heightened security and carry on with their heinous acts undetected.

In the recent past, there have been numerous attacks involving landmines, grenades, or other explosive devices in Mandera, Wajir and Garissa counties by the insurgents.