It was the latest in a series of armed protests which have gripped the country since January, with troops angered by an unresolved dispute over wages and demanding the government of President Alassane Ouattara pay up.
"This is not a coup. We want our bonuses. The president signed a paper saying he agreed with our bonuses. When he pays up, we'll go home," said a spokesman for troops at Bouake barracks, the centre of the latest four-day protest.
"8,500 of us brought Ouattara to power, we don't want him to leave but he's got to keep his word. It's that simple," he added as a group of soldiers, some wearing masks, let off a rattle of gunfire.
Ouattara took office in 2011 after months of deadly election violence in which more than 8,000 rebels supported him against troops backing ex-head-of-state Laurent Gbagbo, who refused to concede defeat at the ballot box.
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Early today heavy gunfire was heard at two military camps in Akouedo in the east of the economic capital, Abidjan, which together form the country's largest military barracks, a resident living nearby said.
Access roads into Akouedo were closed, preventing residents from the east of Abidjan from entering the city, an AFP reporter said.
Shots were also heard from Gallieni camp in the city centre.
Sustained gunfire also rang out in Bouake, the second- largest city, where one person died yesterday from bullet wounds.
The situation was also tense in Man in the west and Bondoukou and Daloa in the centre of the country, where sporadic shooting could be heard.
But there was no immediate sign of any troop movements on the road between Abidjan and Bouake.
Mutinous former rebels often fire in the air to express their anger over the non-payment of bonuses by the government.
The African Development Bank advised its employees in Abidjan to stay at home, warning that the security situation remained unclear.