Just over a week after a failed coup, the crisis in Burundi deteriorated sharply with escalating violence and the weekend assassination of an opposition leader.
Thousands of activists carrying placards Sunday mourned the death of Zedi Feruzi, leader of the small Union for Peace and Development party. He was buried during the day as opponents of President Pierre Nkurunziza's bid for a third term in office vowed to continue protests.
The mourners carried placards with phrases that included "We are tired" and "Nkurunziza, go. No to a third term."
Observers fear the small central African nation is sliding dangerously toward another civil war, with Nkurunziza determined to cling to power despite widespread opposition. The country emerged from more than a decade of war in 2006.
Nkurunziza insists his bid for a third term doesn't violate the constitution, as opponents allege. He says he is entitled to one more term in office because he was elected by parliament, not the public, the first time around.
Feruzi was shot by men wearing uniforms similar to those of the presidential guard who pulled up in a car, opened fire and sped off, Burundi radio journalist Jean-Baptiste Bireha told news agencies. He was with Feruzi and witnessed the attack.
The killing sent waves of shock through the nation's opposition, with fears that other opponents of the third-term bid could be targeted in coming weeks.
Feruzi's assassination came after a grenade attack Friday in the central market in the capital, Bujumbura, that killed two people and injured dozens. Dozens more people have been killed in recent weeks when police opened fire on protesters demonstrating against the third term.
Nkurunziza is pressing ahead with presidential elections next month, ignoring international pressure, including from African leaders, calling on him to delay a vote until the country is peaceful and stable. U.S. and African Union leaders say his bid flies in the face of the constitution.
After Feruzi's assassination, some opposition leaders went into hiding, warning that anyone who opposed Nkurunziza's reelection effort could be killed, the Associated Press reported.
"The life of anyone who opposes Pierre Nkurunziza is in danger. People are being assassinated here and there," an opposition leader, Agathon Rwasa said, according to AP.
The presidential office expressed shock at Feruzi's killing and denied any role. Police blamed Friday's grenade attack on protesters opposed to Nkurunziza's plans, but organizers reject the accusation.
U.N. Secretary-General Ban Ki-moon condemned Feruzi's assassination and the grenade attack in a statement Saturday, warning that the two events would deepen mistrust and lead to further violence.
He urged Burundian authorities to bring those responsible to justice and called for calm and restraint.
He also called on Burundian authorities "to uphold the human rights of all Burundians, including the freedoms of assembly, association and expression, and to take concrete steps to prevent political killings and violence."
Nkurunziza was in the Tanzanian capital Dar es Salaam on May 13 to discuss the crisis generated by his election plans with African leaders when Maj. Gen. Godefroid Niyombare announced the president had been dismissed in order to usher in peaceful elections. After brief fighting in the capital for the control of the state-owned radio and television station, the coup was defeated.
But four independent radio stations were attacked and forced off air during the fighting, leaving only state radio and television operating in a country where most people get their news from radio.
Niyombare escaped but 17 other officials have appeared in court on charges of plotting the coup.
At least 100,000 people have fled the violence in Burundi for neighboring countries since the crisis began.