Updated

Hundreds of residents fearful of a government backlash over the weekend killing of at least 34 police officers are fleeing their homes in northwestern Kenya as security officers said a serious operation is under way to pursue the bandits, officials said Tuesday.

Police Commissioner Mathew Iteere said a "serious" operation has begun to find those responsible for the deaths of nearly three dozen officers over the weekend.

"We cannot allow such things to happen. I think they were testing the waters and in due cause they will know the depth of the river," he said.

Residents in Baragoi, the main town in Samburu North district, said there was massive build-up of police officers in the town.

The police were killed over the weekend after being ambushed by bandits from the Turkana tribe who are suspected to have stolen cattle from the Samburu tribe.

Samuel Letipila, who represents the affected area in the local council, said 34 bodies of police officers and reserves had been recovered. Iteere put the confirmed death toll at 32 with several officers missing.

Letipila said he lost 112 cattle in mid-October when the Turkana raiders stole more than 500 cattle. Twelve Samburu warriors were killed on Oct. 30 when they attempted to recover their animals from the Turkana. Those killings led to last weekend's police operation, he said.

Francis Karimi, a local government official in Baragoi, said nearly 1,500 members of the Turkana community had fled from the village of Lemerok over fear of an upcoming government operation. Karimi said residents could be seen leaving in buses with their mattresses and boxes of household goods.

"They are afraid," Karimi said.

The region where the killings took place, the Suguta Valley, is far removed from modern society. Roads and communications are bad, and few security officers are stationed there. Security officials operating around the Suguta Valley area say it is the perfect hideout for bandits because it gives them a fort-like defensive position and the rugged terrain works to their advantage.

Peter Lekeren, a Kenya wildlife Service warden in the area, described the Suguta Valley as "one way in and one way out and high elevation on either side of entrance and exit."

"If the bandit gets to the valley before those pursuing them it becomes impossible to capture them. They climb on the hill and mow down anybody attempting go through the entrance of valley," he said.

Kenya's police spokesman on Monday said the bandits had the high ground against the police, resulting in the massive number of deaths.

Lekeren said temperatures in the valley can get to 40 degrees Celsius (104 Fahrenheit) and can be unbearable for those who are not accustomed to it. He said the bandits are usually armed with automatic rifles.

Cattle rustling between the Samburu, Turkana, Pokot and Markwet tribes -- pastoral communities -- is a traditional practice associated with coming-of-age rituals and is meant to replenish a community's stock of livestock after droughts and famine. But the introduction of guns into a practice once dominated by spears and arrows has led to higher death tolls. The guns are smuggled through Kenya's porous borders with Somalia and South Sudan.

A 2010 report by Kenya Human Rights Commission said that in the past three decades, the motive behind cattle-rustling and its modus operandi has significantly changed. The traditional practice has been increasingly replaced by the criminal activities of livestock theft, the report said.

It said that marginalization of the pastoral communities, both during the colonial and post-colonial periods, has led to the underdevelopment and higher poverty levels in these regions, which has in turn resulted in higher levels of insecurity.

The weekend slaughter -- and the high-powered guns the tribesmen used in the attack -- raises concerns that Kenyan officials will not be able to stop violence during the country's next presidential election in March. Kenya police struggled to contain violence that broke out following the dispute over who had won presidential election in late 2007. More than 1,000 people died and 600,000 were displaced from their homes in the ensuing violence.

A 2008 government report said one of the reasons violence flared was the lack of trust in public institutions, including the police, which was seen as taking sides in the conflict. Kenya is currently attempting to reform the police force partly to ensure that violence does not recur during the March elections.