Hundreds of teachers in northern Kenya bordering Somalia have refused to return to work, fearing attacks by Islamic extremists, a union official and teachers said Tuesday.

The estimated 700 teachers demonstrated outside parliament in Nairobi demanding that the government transfer them to schools in safer regions.

The protesting teachers were from Wajir, Mandera and Garissa, where most of the residents are Kenyans of Somali ancestry, said the Kenya National Union of Teachers Chairman Mudzo Nzili.

The demonstrating teachers are non-Somali and fear for their lives following attacks that singled out non-Somalis by the Somali militant group al-Shabab, he said.

"We are so traumatized. I buried 10 colleagues in one week . . . It is very difficult for me to think of going back there. We should be transferred," said Anne Nyakio, a teacher from Wajir Girls High School.

In November al-Shabab attackers hijacked a bus near the town of Mandera, singled out non-Muslims and non-Somalis, and shot dead 28 passengers. Twenty-two of those killed were teachers. Ten days later al-Shabab massacred 36 quarry workers who were non-Muslims.

Kenya's schools re-opened almost two weeks ago following a nationwide teacher's strike over wages that delayed the resumption of classes after the Christmas vacation.