Kenyan security personnel are in hot pursuit of al-Shabaab militants who killed six people in Kenya's north-east early Thursday, government spokesman Eric Kiraithe said.
The attackers stormed into a residential plot in the town of Mandera near the Somali border, using a grenade to break the entrance and firing randomly at residents, the newspaper Daily Nation reported.
Police intervened and the attackers threw another grenade before they escaped, according to the report.
"Six out of the thirty-three occupants of the attacked premise were killed and 27 rescued by our security forces," Mandera county governor Ali Roba said on Facebook.
Addressing a news conference in Nairobi, Kiraithe said security personnel had received a warning that an attack was about to take place in Mandera, but no information on the target.
Kiraithe said the attackers had crossed the border into Somalia.
Al-Shabaab claimed the attack on pro-insurgent radio Andalus, saying it targeted Christians.
Al-Shabaab frequently targets Kenya its military presence in Somalia, where their troops form part of an African Union contingent helping the Somali government battle the Islamists.