At least three people, including two police officers, were killed on Wednesday in eastern Kenya’s Garissa County in an attack by allegedly conducted by al-Shabaab militants.

According to Nairobi-based The Star newspaper, the two police officers and a civilian were part of a group of people that were in a police vehicle when they were attacked between the Hayley Lapsset Camp and Garissa.

Witness reports indicate that the vehicle ran over an improvised explosive device (IED) planted to demobilize it, before the attackers fired a rocket propelled grenade.

They then fired several rounds of ammunition at the vehicle, killing the three. Other people managed to escape.

Police said they are pursuing the attackers who escaped after the incident.

More officers have also been deployed in the region to bolster security, amid heightened security surveillance in Kenya’s eastern and northeastern regions.

Earlier this month, authorities arrested some al-Shabaab militants who were said to have been escaping Somalia, where an anti-terror campaign has been launched to crush the group.