NAIROBI, Kenya (CNN) -- A massive rally in protest of President Mwai Kibaki's re-election was planned for Friday, one day after the nation's attorney general called for a recount and an independent investigation into the country's disputed election.
An Odinga supporter displays a sign during a march in Kisumu, Kenya, Thursday.
"The level and nature of the violent protest has never before been witnessed in our country and is quickly degenerating into a catastrophe of unimaginable proportions," Kenyan Attorney General Amos Wako said of the country's turmoil.
He called for a government of national unity and said a recount and investigation "will go a long way in assuaging the inflamed passions of the people."
Reports of violence, looting and fires were sporadic in Nairobi's sprawling slums, including Kibera, from which residents had left en masse to Uhuru Park.
Video from Nairobi's outskirts showed streets littered with broken glass, overturned Coca-Cola crates and, in some places, fires. One man carried a sign that read: "Shame on you Kibaki you raped our democracy."
Meanwhile, children's bodies piled up in a Nairobi morgue, churches burned and police on horseback chased pedestrians through the streets.
"What we have just seen defies description," opposition leader Raila Odinga of the Orange Democratic Movement told journalists after visiting one Nairobi morgue Thursday. "We can only describe it as genocide on a grand scale."
Images provided to CNN by I-Reporter Duncan Musicha Waswa showed riot police on horseback chasing citizens on Nairobi's Bunyala Road. Those going about their daily business raised their hands to avoid the wrath of police, Waswa told CNN.
Police on Thursday blocked a march into Nairobi in support of Odinga's party with tear gas and water cannons. Watch a report from the front lines of that protest »
The rally was banned by Kenya's government which had prohibited political gatherings before the December 27 elections.
Earlier this week, the ODM posted on its Web site a call for Kibaki to protect all Kenyans.
At least 300 people have been killed and as many as 75,000 people internally displaced in the post-election violence, the government said.
Kibaki has appealed for calm and on Thursday condemned the "senseless violence," which he said is causing an "unnecessary loss of lives, destruction of property, and displacement of innocent ... from their homes."
"I am ready to have dialogue with concerned parties once the nation is calm and the political temperatures are lowered enough for constructive and productive engagement," he said.
His government has halted all live broadcasts in the country as part of an effort to bring tensions down. The ODM called the order a "direct curtailment of freedom of expression rights that contravenes provisions of our constitution."
Kibaki narrowly won re-election with 51.3 percent of the vote, while Odinga garnered 48.7 percent, the country's election commission announced Sunday.
International observers said the balloting fell short of international standards for democratic elections.
Archbishop Desmond Tutu met with Odinga and other opposition officials Thursday and was scheduled to meet with Kibaki Friday morning, according to the African Council of Churches.
U.S. Secretary of State Condoleezza Rice also has sent diplomat Jendayi Frazer, who was to arrive in Kenya on Friday and meet with Kibaki, Odinga and other political leaders, State Department spokesman Sean McCormack said Thursday.
The deadly violence in Kenya, which had been a stable country in an otherwise volatile region, has sparked international outrage and concern.
U.N. Secretary-General Ban Ki-moon said he was "increasingly troubled" by the reports from Kenya, his spokesman said in a statement on Wednesday.
The European Union and the African Union have both offered their help in mediation efforts, but the government did not immediately welcome those offers.
At least one report indicated that some opposition supporters were targeting the Kikuyu tribe, Kenya's largest, of which Kibaki is a member. The Kikuyu comprise roughly 22 percent of the nation's population, while Odinga's Luo tribe comprises 13 percent.
A local reporter told CNN Wednesday he witnessed youths from minority tribal groups manning checkpoints outside Eldoret, about 185 miles (300 km) northwest of Nairobi, and refusing entry to members of the Kikuyu tribe. Kenyans are required to carry identification cards and a person's name often indicates what tribe they are from. E-mail to a friend
CNN's Matthew Chance, Paula Newton, Kim Norgaard and journalist David McKenzie contributed to this report
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