Up to 29 people have been killed on the Kenyan coast overnight amid mixed reports and claims of responsibility by local militant groups, authorities said on Sunday.
Nine people were gunned down in the town of Hindi in Lamu County on Saturday night, while another 20 were killed in the Gamba area, the Interior Ministry said.
"They went around shooting at people and villages indiscriminately," Abdallah Shahasi, a senior official in the Hindi area told Reuters.
Al qaeda-linked Somali militant group, al Shabab, were quick to stake responsibility for the attacks, as they have done for a spate of recent raids on coastal villages.
Kenyan President Uhuru Kenyatta, dismissed al Shabab's claims of responsibility last month for an attack in the nearby town of Mpeketoni, which left 65 people dead. On Sunday, he echoed his doubts over the militant group's claims, insisting instead that the latest raid was the work of political rivals.
Kenyan police say preliminary investigations point to Kenyan separatist group Mombasa Republican Council (MRC), citing a message on a school blackboard allegedly left by the attackers.
The message suggests the perpetrators support veteran opposition leader and former Prime Minister Raila Odinga. The slogans scrawled on the board also called for Muslims to reclaim the coast and expel Christians from the land, police deputy inspector Grace Kaindi, told reporters on Sunday.
"At first we thought it was al Shabaab, but now it is turning out that it is MRC, as they have put it there clearly," Kaindi said.
MRC Secretary General Randu Nzai Ruwa quickly denied orchestrating the attack, telling Reuters, "The government should stop using us as a scapegoat."
The latest attack came on the eve of a planned protest rally organized by the opposition party leader in Nairobi.
Odinga was defeated in Kenya's most recent election and in subsequent months has held frequent rallies over the government's security record, its handling of the economy and its corruption.
The accusations from both sides have stoked fears of further violence across the nation amid rising tensions between supporters of opposing parties and along tribal lines.
Odinga is choosing to ignore a court order banning him and others from organizing the protest, saying Monday's event will go ahead as planned.
The government said it will deploy a police force of 15,000 to patrol the rally and curb any violence.
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