Burundian President Pierre Nkurunziza stood unopposed Monday as voters went to the polls after a chaotic month marred by an opposition boycott over fraud claims and daily grenade attacks.

The presidential vote is the second phase of an electoral marathon that was supposed to assert the war-scarred central Africa nation's democratic credentials and cement a fledgling peace deal.

Instead, the country's 3.5 million voters were left without a choice of candidates and staring down the barrel of a return to the kind of civil strife that left 300,000 people dead over 13 years.

Burundi's security services had feared a final flurry of grenade attacks but Public Security Minister Alain Guillaume Bunyoni said only three were reported overnight, causing no injuries.

"We only had three grenade attacks in Bujumbura," he told reporters. "The situation is under control. The police and the army are jointly enforcing law and order."

At least eight people were killed and more than 60 wounded nationwide in grenade and other attacks since a bitter political and security crisis was ignited by May 24 local council polls.

The election saw Nkurunziza's ruling party win comfortably and was given the nod by foreign observers but the entire opposition charged the ballot was rigged and subsequently pulled out of the presidential poll.

National Liberation Forces (FNL) leader Agathon Rwasa, whose rebellion only laid down arms last year and was seen as Nkurunziza's main presidential challenger, has since disappeared and is believed to have gone into hiding.

In the southern Bujumbura FNL bastion of Kanyosha Monday, an AFP correspondent said only a handful of voters had turned out to vote, compared to hundreds at the same time a month ago.
  
"An election with only one candidate does not make sense, I am taking my coffee and after that I will go home to rest," said Willy Harerimana, sitting in an internet cafe.

© ANP/AFP