Bujumbura (Burundi) (AFP) - Explosions and gunfire were heard late Monday in Burundi's capital Bujumbura, hours before polls were due to open in a divisive presidential election, in which Pierre Nkurunziza's is seeking a controversial third term.
AFP journalists heard at least three loud explosions and sustained bursts of gunfire, without being able to determine their origin.
There was no information yet on any casualties. Shots could still be heard shortly before 11:00 pm (2000 GMT) but they had become more sporadic.
Witnesses said unknown assailants in the northern Ngagara suburb had opened fire on police officers, who fired back. At least two blasts were heard in the area.
At least two explosions and shots were also heard in Nyakabiga, to the northeast of the city, and Kanyosha in the south, residents said.
Earlier Monday, a grenade was lobbed from a passing car into a street close to the symbolic Independence Square in central Bujumbura. There were no reports of injuries
The attacks come against the backdrop of roiling tensions over Nkurunziza's quest for a third consecutive five-year term.
The opposition has called for a boycott of Tuesday's election, which is going ahead despite months of violent anti-government protests and appeals from the international community for the incumbent to step aside.