The attack took place in the coastal county of Lamu, which borders Somalia and has been hit by a wave of attacks by the Al-Qaeda linked group.
Northeastern regional commissioner Mohamud Saleh said a police four-wheel drive vehicle hit an IED (improvised explosive device) while officers were travelling to Lamu from a neighbouring county to buy supplies.
He said the vehicle was badly damaged but that the officers had been evacuated to the nearby town of Hindi.
The militant group is believed to have fighters operating in the area's Boni forest.
In mid-June 2014 close to 100 people were killed in a series of armed assaults on the town of Mpeketoni and surrounding villages in Lamu county.
These attacks, close to the once-popular holiday island of Lamu, led to a collapse in tourism on Kenya's coast after foreign governments warned their nationals against travelling to the area.