Kenyan police vowed Saturday to intensify patrols along the border with Somalia to thwart al-Shabab attacks.

Police spokesman Charles Owino said security agencies are also on high alert for any possible attack by the militants targeting security installations and any other soft targets along the border between Mandera and Elwak in northeast Kenya.

"This follows the latest development across the border for the past two weeks, in which the militants have been converging close to Kenyan border," Owino said in a statement issued in Nairobi.

He said the buildup has been evident in areas of Hola, Dura, Jidahaley, Juma and Ilkabere in northeast Kenya where the militants have been carrying out terror attacks in recent past.

The statement comes barely a week after the Islamic militants raided a local school in Mandera, killing two teachers.

More than 20 assailants believed to be al-Shabab militants raided teachers' quarters in Arabia Boys Secondary School, Mandera County, about 1 kilometer away from the Kenya-Somalia border, killing the two non-local teachers while two others escaped the death dragnet.

Owino said police operations have established that Hassan Hodey, a Somali national from neighboring area of Damasa, was behind that heinous act.

"Security agencies are pursuing the culprit and will not relent till he is brought to justice," Owino assured.

The police attributed the current movement by the militants towards the Kenyan border to ongoing purge on their bases in Somalia by African Union Mission in Somalia (AMISOM) and allied forces.

"Our officers are on high alert monitoring their movements so as to counter any attempts by these criminals to cross over to our country to cause fear and despondence," said Owino.

He called upon members of the public particularly those living along the border to remain vigilant and report any suspicious movement by individuals or groups to any nearest security personnel.

Security in Mandera remains volatile with the militia who cross over from their neighboring country responsible for the numerous attacks that have rocked the area.

Kenya's northeastern region has suffered the brunt of grenade and gun attacks in the last several years since Kenya took its troops to Somalia to fight the al-Shabab militia group.

Many people, majority of them non-locals, have as a result lost their lives with others left with permanent injuries.