Authorities in the Ivory Coast have arrested 21 gendarmes and seized stocks of weapons after an attack on Abidjan's main gendarme base early on Saturday triggered a gun battle, a pro-government newspaper said on Tuesday.

Gunfire rang out from the Agban paramilitary base for nearly an hour on Saturday. The Nord-Sud daily said dissident gendarmes tried to attack the base but were repelled, underscoring the challenge President Alassane Ouattara faces restoring security to Ivory Coast, still recovering from civil war.

Nord-Sud is close to Prime Minister Guillaume Soro, who is also defence minister and de facto leader of the former rebels who helped oust former president Laurent Gbagbo. Rebels now make up the bulk of Ouattara's military commanders.

Revelations are coming out about an attack on Agban base on Friday through Saturday, the newspaper reported. More than 200 Kalashnikovs, some M16s, PKMs (belt-fed hand machineguns) and grenades have been seized.

It said the 21 gendarmes who were arrested were from the Abidjan base of Koumassi, on the south side of the city's lagoon.

Gbagbo lost an election to Ouattara in November but he refused to step down. The West African nation and top cocoa producer was plunged into civil war that killed 3,000 people and displaced more than a million, until Gbagbo was forced out in April.

Security has dramatically improved since then, but it remains fragile, with gunmen of various loyalties jostling for position and occasionally fighting.

Armed robberies, extra-judicial killings and in-fighting between former rebel factions, all fed by a flood of weapons still in circulation, have marred Ivory Coast's otherwise impressive post-war recovery.

The newspaper quoted senior military sources as saying the attackers shouted threats at the camp before opening fire.

Ouattara says he wants to reconcile Ivory Coast after a decade of crisis and instability divided it in two, but insecurity remains a concern in Abidjan and in the volatile west.

Success will depend on uniting the various pro-Gbagbo and pro-Ouattara factions that make up the new military into disciplined units.