The attacks occurred when militiamen from the Pokomo side raided manyattas at Reketa area in Tana River, and slashed villagers to death before setting their houses ablaze.
“In total 52 people died; they include 34 women, 11 children and seven men,” deputy police chief for Mombasa, Joseph Kitur, said.
Sixty cows were also slashed to death by the attackers during the deadly fighting.
“It is a very bad incident, 34 were hacked to death and we have 14 others who were burnt to death in their houses,” he added, “Our investigations have shown that it is the Pokomos who attacked the Orma people who live at an island.”
The two communities have been fighting over land, pasture and water since last month, but Wednesday’s attack was seen as the worst in their history.
“Our officers are on the ground pursuing the attackers,” he said, but could not confirm reports that some of the perpetrators were already in custody.
Police said tension had been building between the two communities for more than two weeks, but there was no immediate warning on the Wednesday night attacks.
In 2001, at least 130 people were killed in a string of clashes in the same district and between the same two communities about access to land and a river.
“Clashes over pasture have been recurrent in this region,” police spokesman Eric Kiraithe said.
The Pokomo are a largely settled farming people, planting crops along the Tana River, while the Orma are largely cattle-herding pastoralists.
“Our investigations have shown that it is the Pokomo who attacked the Orma people, who live on an island” in the river, Kitur added.
Garsen Member of Parliament Danson Mungatana, who represents the area, said the killings were “revenge attacks”, adding there had been a string of tit-for-tat killings, attacks and cattle raids this month, though on a far smaller scale.
“There have been problems simmering for a while…. About 10 days ago three Pokomo were killed by the Orma community,” he said.
“In revenge, the Orma raided villages occupied by the Pokomo and burnt down more than 100 houses. Now the Pokomo have once again revenged by killing about 50 people. These are purely revenge attacks.”
In 2007 Kenya spiraled into violence after contested elections that left some 1,200 people dead and half a million others displaced.
President Mwai Kibaki issued a statement on Wednesday evening condemning the killing of innocent people in Tana River County.
The president sent a message of condolence to the families, relatives and friends of those who died following the attack.
He said investigations have begun with a view to not only apprehend the culprits but also ensure such heinous acts do not recur.
President Kibaki assured that security had been beefed up in Tana River County to ensure that the lives and property of the residents are protected.
The Head of State, at the same time, wished the injured quick recovery.