Kenya's opposition leader has urged people to stay away from work on Monday over the disputed election result.
Raila Odinga said it would be a "day of mourning for the fallen patriots" after a rally in Kibera, the largest slum in the capital Nairobi.
The international community has urged calm following the vote, which Mr Odinga alleges was fixed.
The official results gave President Uhuru Kenyatta 54.3%, and Mr Odinga 44.8%.
The allegation has sparked violent protests, with the latest reports suggesting at least 16 people have been killed since the result was declared.
The victims included a nine-year-old girl hit by a stray bullet in Nairobi's Mathere slum.
In a tweet sent after the rally, Mr Odinga said they had died at the hands of "Jubilee mandated death squads", referring to Mr Kenyata's party.
A man was also killed in Kisumu county, an opposition stronghold and the centre of post-election ethnic violence in 2007, when 1,200 people died and 600,000 were displaced.
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"This is a failed regime that is resorting to killing people instead of addressing the real issue. The vote was stolen. There's no secret about that," Mr Odinga told the 4,000 people who had gathered to hear him talk on Sunday.
He added: "We had predicted they will steal the election and that's what happened. We are not done yet. We will not give up. Wait for the next course of action which I will announce the day after tomorrow.
"But for now I want to tell you not to go to work tomorrow (Monday)."
The Elections Observation Group (Elog), which had 8,300 observers, said its projected outcome put Mr Kenyatta on 54%, just short of the official figure of 54.3%
On Saturday. Mr Odinga's aide James Orengo questioned Elog's independence.
Others have been urging calm.
Kenya's acting Interior Minister Fred Matiang'i pleaded with people to return to their normal lives and called for Kenyans to use social media responsibly.
Mr Matiang'i said most areas were calm but there had been some violence which he blamed on criminals.Image copyright EPA
Mr Kenyatta has also urged peace. "We have seen the results of political violence. And I am certain that there is no single Kenyan who would wish for us to go back to this," he said.
Ahead of the results, Mr Odinga had called on his supporters to remain calm, but added that he did not control anyone, and that "people want to see justice".
Rights group Amnesty International has called for the Kenyan authorities to investigate the killings.