Thousands have defied a ban on protests, a day after President Pierre Nkurunziza announced his bid for a third term in office, leading to clashes with police.
At least two protesters were killed and more than five were injured, with one in a coma, Burundian Red Cross spokesman Alexis Manirakiza told the BBC.
President Nkurunziza said in his speech,
"I call people to go to the election in peace. But I would like to warn everyone: Whoever wants to create problems with the ruling party elected by the people, he'll find himself in trouble."
The president has served two terms in office, and Burundi's constitution does not allow a third term.
Opponents of the president's party say his bid is unconstitutional and threatens the 2005 peace deal that ended the 12-year civil war, which left over 300,000 people dead.