In Madagascar, some 300 protesters were killed or wounded when security forces opened fired on them on Saturday.
The country's president and his rival each held the other responsible for the escalation of violence.
The protest turned deadly when government soldiers opened fire near the presidential palace in the capital Antananarivo.
Radio stations reported some 30 people were killed including a local reporter and dead bodies can be seen piled up on the city's streets.
The survivors were sent to the city's hospital or private clinics by ambulances, and national police warned the death toll may rise as many of the injured were in a grave condition.
President Marc Ravalomanana appeared on state television later that day to say the loss of life was difficult and said the opposition leader Andry Rajoelina was to blame.
Saturday's protest started when Rajoelina was addressing supporters at a central square. The demonstrators then headed toward the presidential palace and clashed with security forces.
An island nation of 20 million people off Africa's southeast coast, Madagascar is one of Africa's poorest nations, with more than half the population living on less than $1 per day.
Power struggles are not new to the country.
Current president Ravalomanana clashed with the former President Didier Ratsiraka when both claimed the presidency after a disputed 2001 election. Ensuing fighting split the country into two governments, with two capitals and two presidents.
Opposition leader Rajoelina defeated the current president's party in municipal elections in 2007. But he would not be eligible to run for presidency in the next scheduled elections in 2011, because he would not yet be 40, as is required.
Rajoelina has shown a genius for articulating grievances in the country but questions about whether he is offering real solutions have emerged.
