Kenyan Vice President William Ruto orchestrated a campaign of ethnic killings "to satisfy his thirst for power" following disputed 2007 elections, prosecutors said Tuesday at the start of his trial at the International Criminal Court.
Ruto, 46, and co-accused Kenyan radio boss Joshua arap Sang, 38, pleaded not guilty to charges of stoking the worst violence in the east African country since its independence in 1963.
Kenyan President Uhuru Kenyatta, Ruto's former political foe turned ally, goes on trial at the ICC on 12 November. He also proclaims his innocence.
The start of the high-stakes case, with the ICC's reputation on the line particularly in Africa, was largely devoted to Ruto's defence, with his lawyer Karim Khan dramatically asking prosecutors to drop the charges.
Ruto, dressed in a dark grey suit, earlier gave a bemused smile as the ICC's Chief Prosecutor Fatou Bensouda opened her case, while Sang, wearing a light grey suit, shook his head and occasionally smiled.
"Mr Ruto, as a powerful politician," planned the crimes "to satisfy his thirst for political power," Bensouda told the court.
"It is difficult to imagine the suffering or terror experienced by the men, women and children who were burnt alive, hacked to death or chased from their homes," Bensouda added.
"He (Ruto) gathered together an army of... youths to go to war for him in the event the election was lost," Bensouda said.
"When the election was lost, he gave the order to attack."
Ruto came to court voluntarily from Nairobi to face three charges of crimes against humanity for allegedly orchestrating the violence in Kenya, a bastion of stability in east Africa.
Some 30 Kenyan MPs and other supporters welcomed the two accused as they arrived for the trial that has been painted as political by critics in Kenya.
The ICC has come under increased pressure globally, especially from the 54-nation African Union, which has accused the court of targeting the continent on the basis of race.
Lawmakers in Kenya last week became the first in the world to approve moves to withdraw recognition of the 10-year-old court that so far has only one conviction under its belt.
Any move by Kenya to leave the ICC's Rome Statute will have no effect on the current trials, but observers fear it may spark an exodus of African member states from the treaty, noting that all current cases stem from conflicts on the continent.
Ruto and Sang each face three counts of murder, deportation and persecution after a wave of violence swept Kenya in 2007-08, leaving at least 1,100 dead and more than 600,000 homeless.
The violence, which laid bare simmering ethnic tensions, was mainly directed at members of Kenya's largest Kikuyu tribe, who were perceived as supporters of then president Mwai Kibaki's Party of National Unity (PNU).
Initial attacks quickly led to reprisals, with homes torched and more people hacked to death.
The two trials are expected to be staggered, set for four weeks at a time, so that Ruto and Kenyatta are not away from Kenya at the same time.
The cases have been mired in accusations of witness intimidation, allegations dismissed by the defence even though several witnesses pulled out.
Ruto's defence lawyer Khan on Tuesday sought to punch holes in the prosecution's case, charging that the probe, initiated by the ICC's previous chief prosecutor Luis Moreno-Ocampo, was based on lies and deception.
"The rotten underbelly of the prosecution's case has been exposed," Khan told judges, showing the court several videos in which Ruto is portrayed as pleading for peace after the December 2007 election.
In one video, when asked about having to come to The Hague, Ruto said: "I have done nothing wrong. My conscience is clear."
More than 300 victims of the violence have been authorised to participate in the proceedings against Ruto and Sang.
There is concern in Kenya that the trials could re-open old wounds and undo reconciliation efforts by communities who once fought each other in deadly battles.
Sang's defence is to launch its case on Thursday, while the first prosecution witness is expected to start testimony next Tuesday.