International organisations appealed for calm on the eve of a presidential election in Democratic Republic of Congo already tainted by deadly street clashes and a showdown between security forces and the main opposition candidate.
The European Union and the United Nations called for restraint after at least three people were killed in clashes on Saturday, the last day of campaigning, putting in doubt the central African state's ability to ensure a representative vote in its second post-war presidential contest on November 28.
The security forces should refrain from any acts that could heighten tensions and create any difficulties on the eve of elections, Mounoubai Madnodje, spokesman for the U.N. peacekeeping mission, said.
The EU observer mission accused the Congolese police of denying President Joseph Kabila's main rival, Etienne Tshisekedi, his right to campaign in the capital after he was blocked at the airport on Saturday.
Police had earlier banned rallies after violence erupted in the capital Kinshasa. The confirmed toll for Saturday's violence has risen to three, according to U.N. human rights sources.
Kabila and the head of the election commission are both due to meet ambassadors in Kinshasa on Sunday. The election commission said on Saturday the vote will take place but poll observers fear many voting centres will not have ballot papers.
Congo's last war ended eight years ago, leaving at least 5 million dead, but the peace is fragile, with pockets of clashes across much of its east while ordinary Congolese complain of rampant corruption and sluggish development.
U.N. peacekeepers on Saturday failed to end a showdown between veteran opposition leader Tshisekedi and the police on Saturday, who blocked him at the airport and fired bullets to disperse his supporters.
Kinshasa is a Tshisekedi stronghold and Reuters reporters saw tens of thousands of his supporters on the streets of the capital after the 78 year-old called for them to try and reach the airport where he was blocked.
Tshisekedi was later driven home by the police, and Albert Moleka, one of his spokesmen, said at least 25 of his UDPS party supporters had been arrested.
Authorities had earlier cancelled campaign rallies that were due to take place in close proximity of each other as violence flared in the teeming city of 10 million people.
The EU observer mission in Congo criticised the authorities for mishandling the end of the campaign period and called the police operation to prevent Tshisekedi from leaving the airport a serious impediment to his right to campaign.
Preparations for the poll have been marred by delays at all stages at the process, with ballot papers being delivered late and many voters unsure where they are meant to be voting.
There were reports of trouble elsewhere in Congo.
A security source said one soldier was killed when the Vangu military camp in the mining capital, Lubumbashi, was attacked overnight by unknown arsonists.
A government building was also attacked on Saturday in the southern town of Kananga by people suspecting local officials of hoarding ballot papers in preparation for rigging the poll, a U.N. official said.
(Writing by David Lewis; Editing by Ruth Pitchford)