Ivory Coast's prime minister says a UN-backed scheme to issue ID papers to some 3.5m unregistered people will continue despite recent unrest.
There have been protests since the scheme was introduced
Charles Konan Banny said nothing could justify the violence in the south where one person died in clashes on Sunday.
Backers of President Laurent Gbagbo fear northern rebels could use the plans to register many immigrants in a bid to favour the opposition.
The process must be completed before elections due in October can go ahead.
The issue of identity was one of the main triggers for the civil war that started nearly four years ago. The rebels say they are regarded as foreigners.
Some 10,000 French and United Nations peacekeepers monitor a buffer zone between the rebels in the north and the government-held south.
One person was killed and several injured in the violent protests in the southern town of Divo on Sunday.
The UN says the scheme must go ahead before elections can be held
"I saw people attacking each other. I saw one dead person and other people injured. They were throwing stones and then there were clubs, iron bars and machetes, and by the end there were gun shots," Reuters news agency quoted an official as saying.
Under the plan, hearings are to be held to determine who will receive papers.
The president of Mr Gbagbo's FPI party told AFP news agency that the clashes started after local officials decided not to carry out identifications.
But speaking on national television, Prime Minister Konan Banny said all necessary measures had been taken for the operation "to be carried out in complete security and transparency and to enable us to fight against fraud".
"Nothing justifies the tension that our country is subjected to, nothing justifies the violence," he was quoted by AFP as saying.
In the main city of Abidjan, there were protests last week against the scheme which brought the city to a standstill.
But rebel spokesman Cisse Sindou dismissed fears that the New Forces rebels were using the scheme to register foreigners to skew the electoral roll in their favour.
"Those are false accusations. Nobody is interfering with the process, which has been implemented by the government of reconciliation," he told the BBC's Network Africa programme.
"The only reason that those people want to boycott the investigation process is because the government of the FPI is a minority government. They know that if there is a proper registration process there is no way they can win elections."
Mr Sindou said ID scheme was running smoothly in rebel areas, where 18 mobile courts were issuing about 2,000 citizenship papers a day.
Last week, President Gbagbo strongly criticised the UN mission, saying it was biased in favour of rebels.