A fire broke out in an electoral commission building in Kinshasa in the Democratic Republic of Conco(DRC) on Thursday, ten days before presidential elections that have been foreshadowed by violence.

The blaze destroyed thousands of voting machines and ballot boxes that were due to be used in the election, a presidential adviser said.

Barnabe Kikaya Bin Karubi said 70 percent of the equipment due to be used for voting in Kinshasa, the country's capital, was destroyed in the fire he said was started by "criminals".

"The enemies of democracy have stepped it up a gear," he said.

Kikaya said that the police guarding the warehouse had been arrested and that preparations for the vote, which could mark the country's first peaceful transfer of power, would go ahead as voting machines from elsewhere in the country would be recalled to be used in Kinshasa.

Congo's first use of voting machines on December 23, a rarity in Africa, has caused concerns among the opposition, diplomats and experts about possible manipulation in favour of President Joseph Kabila's preferred successor. Kabila is stepping aside after taking power in 2001.

The fire broke out around 2am in a building where election materials were being kept, the head of the Independent National Election Commission (CENI) said.

A thick cloud of black smoke was still visible above the city by early morning, the AFP news agency reported.