NAIROBI — Kenyan authorities said suspected al-Shabab extremists killed three teachers in an overnight attack Friday in the northeastern county of Wajir, while police said they foiled another attack in the east, killing a suspect and recovering a huge cache of weapons.

Gunmen attacked Qarsa primary school and targeted non-Muslim teachers, North Eastern regional coordinator Mohamud Saleh said. A responding rescue team ran over an improvised explosive device but no one was injured, he said.

Education along Kenya's border with Somalia has been greatly hindered after many non-Muslim teachers refused to work in the region following the extremist group's targeting of non-Muslims starting in 2014 that left dozens dead.

The Somalia-based Al-Shabab has vowed retribution after Kenya sent troops in 2011 to fight the extremists in the Horn of Africa nation.

In the foiled attack in Merti in Isiolo county, police killed a suspected al-Shabab extremist and recovered a cache of weapons in his vehicle on Thursday, a police official said. At least 1,000 bullets, 36 grenades, 18 bombs and five rifles were recovered and two other suspects believed to be al-Shabab members were in custody, the official said.

Police have yet to determine the target for the attack, said the official, who spoke on condition of anonymity because they were not authorized to give details of an ongoing investigation.

Also on Friday, the wife of a slain Muslim cleric was sentenced to 10 years in prison for the attack by three women on a police station in the coastal city of Mombasa in 2016.

Haniya Saggar was found guilty of facilitating the women, who police said petrol-bombed the station and stabbed an officer before being shot dead.

Saggar is the widow of Sheik Aboud Rogo, who had been arrested in connection with the 1998 U.S. Embassy bombings in Kenya and Dar es Salaam that left over 200 people dead but was never convicted. He was shot dead in 2012 by suspected government agents.

AP