A suspected member of Somali Islamist group al Shabaab detonated an explosive device that killed two people at their home in a western Kenyan village and himself, police said, outside the group's usual of area of operations.

If the affiliation between the suspect and the al Qaeda-linked al Shabaab is confirmed, it will underscore the group's push to recruit members of more diverse backgrounds to carry out attacks over wider territory.

Al Shabaab is fighting to overthrow Somalia's central government and regularly launches attacks in Kenya to the west in retaliation for Kenya contributing troops to an African Union peacekeeping force in Somalia.

But this attack was in the far west of Kenya, hundreds of kilometres from the Somali border.

Police said the attacker went into a home in Kamloma village in Kisumu County late on Tuesday and questioned a mother, father and daughter.

"The al Shabaab suspect started questioning them on things they didn't understand. Suddenly an improvised explosive device he was carrying exploded, killing the suspect," police said in a report.

Only the daughter, who was seriously wounded, survived, police said.

Police officials did not return calls seeking comment on the attacker's suspected links to al Shabaab.

Al Shabaab's attacks in Kenya include a 2015 assault on a university that killed 166 people and a 2019 attack on a Nairobi hotel and office complex that killed 21.

The 2019 attack was the first led by a Kenyan gunman who was not an ethnic Somali, a result of al Shabaab's efforts to recruit more foreigners.

Reuters