Suspected Al-Shabaab fighters have beheaded there people and torched houses in dawn attack on Maleli Village of Witu in Lamu.
Villagers and sources on the ground put the figure at four but County Commissioner Gilbert Kitiyo told the Nation that the report he had received indicated three.
Mr Kitiyo said he had dispatched a contingent of police officers to pursue the attackers.
The gunmen struck at around 12.30am Friday as the villagers slept, according to witnesses.
Armed to the teeth, they targeted men as they spared women and children, villagers told the Nation.
They disappeared into the bushes as has been their tactic in past attacks.
The government believes the militants have set up hideouts in the expansive and dense Boni Forest and a multi-agency operation is ongoing to flush them out.
Al-Shabaab, the Somalia-based rag-tag militia linked to Al-Qaeda terror network, has been attacking villages and ambushing travellers in the coastal county for months now.
The militants fighting to impose an Islamic caliphate on Somalia have also been planting explosives on roads in Lamu, Garissa, Mandera, Tana River, Wajir and other parts of Coast and northern Kenya to avenge deployment of Kenyan military to the war-wracked country.
Last week, a roadside bomb killed five police officers in Ijara, Garissa County.
The Kenya Defence Forces are part of the African Union mission that has routed the militants out of major towns across the Horn of Africa state.