An armed gang attacked a village in strife-prone western Ivory Coast, leaving at least six people dead, including two soldiers, an army officer said Thursday.

"An attack against the village of Zilebly overnight on Tuesday led to the death of six people, including two members of the FRCI (the Ivory Coast Republican Army)," the officer said, asking not to be named.

A local journalist said two soldiers and six civilians died. Both he and the army officer blamed assailants who crossed the border from Liberia, which lies just three kilometres (two miles) from the village.

"Calm is restored, but thousands of people have fled the area to take refuge in the nearby towns of Blolequin and Toulepleu," said the journalist, who went to the scene.

UN sources confirmed that thousands of people had fled the violence.

The spokeswoman for the UN mission in Ivory Coast, Sylvie van den Wildenberg, said "several people" had been killed in the attack, which she said had been carried out by "several dozen unidentified armed men".

"Houses were burned and looting carried out," she told AFP, saying the UN mission condemned the attack "in the strongest terms".

"(Violence) in certain regions remains a major concern in the run-up to the regional and municipal elections" scheduled for April 21, she added.

Racked for years by tensions caused largely by land disputes, western Ivory Coast was the most violent region during the country's post-election crisis in 2010-2011, which claimed about 3,000 lives.

After the crisis -- triggered by the refusal of former president Laurent Gbagbo to admit an election defeat to Alassane Ouattara -- the region was targeted by armed groups based in eastern Liberia.

Seven UN peacekeepers were killed in one of these raids, in June 2012.

Ouattara's government has accused armed exiles loyal to Gbagbo of carrying out the attacks, but the former leader's supporters deny any involvement.

Gbagbo himself is now behind bars at the International Criminal Court in The Hague, facing charges of crimes against humanity.

Ivory Coast and Liberia have agreed to tighten border security, with the aid of UN forces present in both countries. Calm had been re-established for several months prior to this week's attack.

Security and national reconciliation remain priority challenges for Ouattara's regime, in the west as well as in the economic capital Abidjan, where attacks also took place against the security forces and strategic sites in the second half of 2012.