Police said gunmen, apparently part of the same group that massacred close to 50 people in the town of Mpeketoni overnight Sunday, attacked a village in the same region overnight and left 10 dead.
"We carried out another attack last night. We killed 20 people, mainly police and Kenyan wildlife wardens. The commandos have been going to several places looking for military personnel," Shebab's military spokesman, Abdulaziz Abu Musab, told AFP by telephone.
"The commandos have fulfilled their duties and returned peacefully to their base," he added, without saying if the attackers were still in Kenya or had driven back across the Somali border, around 100 kilometres north.
"Our officers are trying to access the scene and the details are sketchy," she said.