The police in Nigeria on Friday said it was making relentless efforts to stop recent attacks by hoodlums on schools in north Nigeria's Kaduna state.

State police chief Ali Janga, who gave the assurance in a statement reaching Xinhua, said security personnel are working round the clock to tame the recent change of tactics by the enemies of peace who now resort to soft targets.

A local security source had told Xinhua on Thursday that a group of unidentified gunmen attacked a secondary school in north Nigeria's Kaduna, abducting the principal of the school.

The incident came barely a week after the abduction of six female pupils and two staff of the Engravers College, in Chikun area of the state.

Janga said the police would prevent future occurrence of such unfortunate incidents, urging parents not to be deterred by the recent attacks.

The state of Kaduna, as well as other states in Nigeria's northwest region, had witnessed a series of attacks by armed groups in recent months.