Congo Republic voted on Sunday in a referendum to determine whether 71-year-old President Denis Sassou Nguesso can legally stand for a third consecutive term in next year's election.
Sassou Nguesso is the latest long-serving African president to pursue legal action to prolong his grip on power. Several other such bids have provoked violence, and four died in Congo last week when security forces opened fire on protesters.
Opposition calls for a boycott and lack of voting materials combined to reduce voting to a trickle at many polling stations in the capital, witnesses said. In some places, the only voters were members of the security forces.
"The people are the only ones who can decide," Sassou Nguesso said as he voted in Brazzaville. "It would have been better if the opposition had not asked its supporters not to vote. But they are also Congolese and we will be bear with them."
Dozens of residents moved from southern neighbourhoods of Brazzaville to other areas on Saturday to avoid possible conflict, although several said they were worried they would not be able to vote as a result.
Sassou Nguesso has ruled the oil-producing country for 31 of the past 36 years and is expected to stand if permitted. He won disputed elections in 2002 and 2009, and under the present constitution term limits and his age bar him from running again.
Last October, Burkina Faso's leader of 27 years was toppled by protests, and the president of Burundi won a third term in July amid violent protests. Rwanda and the Democratic Republic of Congo have also sought constitutional change.
The legal changes offer a challenge for Western governments: they can endorse veteran leaders or press for term limits. Congo is a former French colony and President Francois Hollande said last week Sassou Nguesso had the right to consult his people.