Kenyan soldiers participate in a joint military exercise with US Marines (not in photo) 15 january 2004 at Manda Bay near the coastal town of Lamu. The exercices are aimed at improving the Kenyan force's "crisis response". (Photo by SIMON MAINA / POOL / AFP)

Kenyan police have launched a manhunt for six al-Shabab militants who attacked a commuter bus in Wajir county near the Somalia border on Wednesday.

The police said the militants who were armed with AK-47 rifles stopped AlMukaram Bus which was heading to Nairobi from Mandera in northeast Kenya and robbed a bus conductor of 40,000 shillings (364 U.S. dollars) and valuables from passengers.

“They fired one shot into the air and ordered all the passengers who were on board to alight from the bus. They separated men and women and interrogated men by asking whether they carry non-locals (Christians) in their buses and also among them whether there was any civil servant,” the police said in an incident report filed on Tuesday evening.

According to the police, the militants took some foodstuff after robbing the bus conductor of some cash and warned him not to carry non-locals on their bus.

The police said the extremists later released the bus to proceed with their journey without harming any of the commuters.

The same stretch (Kotulo area) has been troublesome for days as the al-Shabab militants stage attacks on separate days leaving a trail of deaths and destruction.

The police said more security officers have been dispatched to the scene to pursue the attackers believed to have crossed into the porous border from neighboring Somalia.

The Somali militants have been abducting civilians and targeting military and police vehicles either by laying an ambush or planting explosives on the road in the northeast region especially in Mandera and Garissa counties.

Many people, the majority of them non-locals or Christians have as a result lost their lives with others left with permanent injuries as a result of attacks staged by the militants.