KERINGET, Kenya -- At first the violence seemed as spontaneous as it was shocking, with machete-wielding mobs hacking people to death and burning women and children alive in a country that was celebrated as one of Africa's most stable.
But a closer look at what has unfolded in the past three weeks, since a deeply flawed election plunged Kenya into chaos, shows that some of the bloodletting that has left more than 650 people dead may have been premeditated and organized.
Leaflets calling for ethnic killings mysteriously appeared before the voting. Politicians with both the government and opposition parties gave speeches that stoked long-standing hatred among ethnic groups. And local tribal chiefs held meetings to plot attacks on their rivals, according to some of them and their followers.
As soon as the election results were announced, handing a suspiciously thin margin of victory to Kenya's president, Mwai Kibaki - whose policies of favoring his own ethnic group have marginalized about half the country - all the elements aligned for an explosion of violence.
Thousands of young men swept the countryside, burning homes and attacking members of rival ethnic groups. And the killings go on. On Friday, six fresh corpses arrived at a morgue in the town of Narok, northwest of Nairobi, some with deep spear wounds. On a strip of white medical tape affixed to the victims' foreheads was written their names, dates of death and the cause: "post-election violence."
"It wasn't like people just woke up and started fighting each other," said Dan Juma, the acting deputy director of the Kenya Human Rights Commission. "It was organized."
What is not clear is if there was a systematic plan to launch a nationwide ethnic war, and whether high-level political leaders played a role beyond possibly inciting violence through hate speech.
Before the election, it was easy to forget that even Kenya, with its reputation as an African success story and land of tolerance, is split along ethnic lines that are ripe for political manipulation. The grievances, typically about land, economic opportunity and political power, are real and often justified, though usually held in check.
Nowhere are those tensions more evident than in the Rift Valley of western Kenya, which has some of the most fabled and productive land in Africa but where tens of thousands of people are fleeing ethnic violence.
The violence out here is decidedly different from that which grinds on in Kenya's slums, where police officers have opened fire on unarmed demonstrators and rival gangs prowl the alleyways with rocks in their hands.
In the Rift Valley, those who have participated in the killings say the attacks have been community efforts, sanctioned by elders and guided by traditions that celebrate a warrior culture.
But government officials may have also been involved.
About a month before the election, police found a large weapons cache - 20 bows, 50 arrows, 30 clubs, 30 machetes and 30 swords - in a government car belonging to an assistant minister and member of the president's political party.
The assistant minister, who was not in the car at the time and has denied involvement, has yet to be charged.
In any case, several residents in the Rift Valley and local aide workers said parliamentary candidates had been arming young men, though no arrests have been made.
Although authorities have not produced any evidence directly linking top politicians to violence, human rights groups documented speeches by political leaders bashing certain ethnic groups in the runup to the election. William Ruto, a charismatic opposition leader and Kalenjin chief, was quoted talking about Kikuyu domination. Kikuyu politicians, meanwhile, made disparaging remarks about Luos and how Odinga, a Luo, was not fit to rule because he was uncircumcised.
At the same time, fliers appeared in several towns in the Rift Valley telling Kikuyus to leave the area.
"Warning! Warning! Warning!" read one flier, "Anyone who does not obey will die."
In some cases, the literature appeared to be part of a campaign of dirty tricks to tarnish rival groups.
The government is blaming opposition supporters and their leaders for the Rift Valley violence, especially the incident in which up to 50 women and children seeking sanctuary in a church were burned alive.