In the arid northern corner of Kenya, bordering Somalia and Ethiopia lies a growing frustration.

It is largely because of the increasing strength of the Al-Qaeda-linked Al-shabaab jihadist group. Some 1,000 kilometers from the capital, Nairobi, the Mandera County is increasingly coming under the control of Al-Shabaab.

''We left the town at about 6am but after some time, when we had reached a solar power center, security vehicles came speeding and police officers asked us to return to town. The police have told us nothing since the incident, we are here waiting for communication from them", said bus driver, Mohamed Bardad.

Last month, the governor of the county of Mandera, Ali Roba published a long letter over terror cells in the county. He accused the government of ''failing miserably'' at stopping them. In response, the northeastern regional commander defended government’s security investment. Schools are shut due to the exodus of teachers and travel has become risky over armed attacks and roadside bombs.

"Problems of security are still there. We have challenges. Al-Shabaab was the problem that has made our teachers, colleagues from other regions to flee this county", Kulo Mohamed, Mandera Teachers' Union Representative said.

Mandera, is one of the least developed counties in Kenya. The governor said 126 schools are yet to reopen due to insecurity. There have been several attacks on ''non-local" teachers in the largely Muslim area in recent years.

Adding to the woes of Mandera residents, a complex internal Somali political crisis that has drawn in Kenya has also led to episodes of fierce fighting on the frontier. Last month, 12 people were injured when a missile hit a house in Mandera.

Nairobi and Mogadishu have had a falling out over Kenya's support of the leader of the semi-autonomous Jubaland region on the border. The leader of the central Somali government tried and failed to get rid of in an election last year.