The Islamist militant group said it had targeted Christians.
Many died in their sleep, the Kenya Red Cross said. The raid, in the town of Mandera, mirrored one in the same county in December in which 36 quarry workers died.
Al Shabaab has made a series of deadly incursions into Kenya, saying it will continue until Nairobi withdraws troops from an African Union force fighting the militants in Somalia.
The group’s military operations spokesman, Sheikh Abdiasis Abu Musab, told Reuters its gunmen killed more than 10 Kenyan Christians in Tuesday’s raid. It has in the past singled out non-Muslims for execution-style killings.
“The area … is a plot where quarry workers live. They attacked at around 1 a.m. Most of those killed are workers from upcountry,” Alex Nkoyo, commissioner for Mandera County, told Reuters by phone. He put the death toll at 14, including a woman who had tried to plead with gunmen before being shot.
In a separate incident, al Shabaab claimed it had attacked a Kenyan military convoy between Mpeketoni and Lamu on the north coast, an area of previous attacks. But an army spokesman denied there was any assault on one of its convoys.
A police commander in the region said a convoy of five civilian buses with a security escort was attacked but no one was hurt. He did not give further details
The raids will heighten pressure on President Uhuru Kenyatta to beef up security in response to al Shabaab attacks, the worst of which killed 148 people at a university in eastern Kenya’s Garissa County in April.
“This attack is a clear reminder that al Shabaab and its collaborators are determined to disrupt and subvert our way of life,” Interior Minister Joseph Nkaisserry said in a statement about the Mandera raid.
He said security forces reacted swiftly to prevent a higher death toll after the group opened their attack by blowing up an entrance gate to the residential area.
After the Garissa attack in April, critics accused the security forces of responding too slowly.
Kenya’s northeastern border with Somalia is widely considered a security weak spot, given the challenge of policing such a long frontier, poor coordination between security services, and a culture of corruption that allows anyone prepared to pay a bribe to pass unchallenged.
Al Shabaab aims to topple Somalia’s Western-backed government and wants to impose its own strict version of Islamic law on the country.