MOMBASA (Kenya), Gunmen killed two female employees of a university in Ukunda, near Mombasa on Kenya’s Indian Ocean coast in a suspected extremist attack, a Kenyan police official said.

The assault occurred as President Uhuru Kenyatta campaigned in the coastal region for the rerun of presidential elections later this month.

The gunmen, suspected to be Al Shabaab rebels from neighboring Somalia, sprayed a vehicle carrying university staff and police with bullets near the campus, said regional police chief Larry Kieng.

Two female staff members of the Technical University of Mombasa were killed in the attack, Mwangi Kahiro, acting county commissioner for Kwale County, said in a statement.

Two police officers who were in the car were also injured and rushed to hospital in critical condition. The officers were escorting the staff when they were ambushed by the assailants, Kieng said.

He said the injured police officers managed to repulse the motorbike-riding attackers who had targeted to rob their rifles.

Police believe the suspects were behind the killing of two police officers on Sept 3 in Kwale.

The officers were killed in an attack at a local church in Ukunda and their rifles were taken by gunmen.

Students held demonstrations following the shooting, condemning insecurity in the region.

The attack recalled the April 2, 2015, attack on Garissa University in eastern Kenya in which four gunmen killed 148 people, most of them students.

Somalia’s Shabaab militia has been carrying out attacks on Kenya as retribution for Kenya’s deployment of troops in Somalia to fight the rebels.

Separately, Kenya’s military said it had gunned down five suspected Shabaab militants in the Bodhei area of Lamu County. The military claimed the five were part of a group that has been terrorizing the coastal area.

Shabaab has claimed responsibility for 16 beheadings in the area since June and dozens of fatalities from roadside bombs.

Kenya is one of six African countries that contribute troops to the African Union force in Somalia to fight the Shabaab, which is waging an insurgency against the U.N.-backed government to establish a state based on strict Sharia law.

The Sabaab is the most potent threat to East Africa’s stability, regaining territory in parts of southern and central Somalia and carrying out frequent attacks in Somalia’s capital and in Kenya, according to the U.S. State Department’s country reports for 2016.

The 22,000 troops in the African Union force pushed the Shabaab out of most of Somalia’s cities and towns but the rebels continued to hold territory in southern Somalia, where the extremist group “gained time and space needed to grow, regroup and recruit new fighters,” the report said.