Now, with violence erupting across the country, many are heeding the call. Several dozen people gathered at the police station in Thika, about 30 minutes north of the capital.
Lillian Ochieng, a Luo, said she was waiting to take a bus to what for her will be safety - in western Kenya.
"Here we are safe by these police, but when we are out we are not safe," she said. "Those boys are beating us. They came from the town and they follow us here and then they throw stones here in the police station. Please, why? Why other places the Red Cross are there, why us?"
The movements by people of different tribes, in reaction to the violence, constitutes a shift in Kenya's demographic distribution. The violence first erupted amid allegations of fraud, following the December 27 national elections. President Mwai Kibaki, a Kikuyu, won a second term and insists the election was legitimate, despite evidence of fraud.
That touched off attacks against Kikuyus in areas where the opposition candidate, Raila Odinga, was popular. Hundreds were killed and tens of thousands were forced to flee to areas of central Kenya where Kikuyus are the majority.
Today, after Mr. Kibaki and Mr. Odinga entered into formal negotiations under the mediation of former U.N. Secretary-General Kofi Annan, Kikuyus, bitter about the treatment of their tribesmen, are forcing out Odinga's fellow Luo, as well as the Luhya and Kalenjin ethnic groups.
In the Witeithe slum on Thika's outskirts, Luos and Luhyas packed their meager belongings into trucks as they prepared to move. One Luo woman said she had nowhere to go and was unsure if she would leave or not.
A young Kikuyu man, John Kimani, looked on as the woman spoke. Later he vented his anger at Luos.
Kimani tells VOA News he is furious at the attacks on Kikuyus and he will ignore Mr. Kibaki if the president tells him not to attack. He says if the woman is not gone by nightfall, he and his fellow Kikuyus will come for her.
It is comments like Kimani's that make people fear that Kenya's violence, which has already killed at least 850 people, might erupt into a wider ethnic war.
The scene was similar west of Nairobi, where hundreds of Kikuyu men blocked the main highway leading from the capital and warned Luos to leave.
Otherwise on Wednesday, the country was relatively free of violence after several days of bloodletting in the cities of Naivasha and Nakuru further north. It is unclear what will happen if efforts at negotiation fail and Mr. Kibaki and Mr. Odinga remain deadlocked.
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