"It's a mutiny by former fighters integrated into the army who are demanding bonuses of 5 million CFA francs ($8,000) each plus a house," a soldier who asked to remain anonymous told AFP.
The protests in Bouake spread to the central towns of Daloa and Daoukro as well as Korhogo in the north, as angry troops took to the streets demanding salary hikes.
Witnesses said the soldiers had left the streets by nightfall except for Bouake, where troops continued to sporadically fire rocket launchers and spray rifle bullets into the air.
"The soldiers are still in control of Bouake. The town is deserted," an AFP correspondent reported.
"There are only soldiers riding in their own vehicles and in government cars."
The government held a meeting of the National Crisis Committee to discuss the situation, a source close to the defence ministry said.
Several dozen trucks and buses were blocked several kilometres (miles) from Bouake on the main road from Abidjan, Ivory Coast's economic capital.
Bouake is the cradle of the armed rebellion that controlled Ivory Coast's north when the country was cut in two between 2002 and 2011.
An army officer in Bouake told AFP that former rebel fighters -- now part of the army -- were behind the uprising.
"It's a mutiny by former fighters integrated into the army who are demanding bonuses of five million CFA francs ($8,000, 7,600 euros) each plus a house," the officer said earlier Friday, speaking on condition of anonymity.
In a statement read out on national television, Defence Minister Alain-Richard Donwahi called on "all soldiers to remain calm and return to their barracks, to enable the search for lasting solutions for every component of Ivory Coast's armed forces."
He said the soldiers were demanding payment of bonuses, salary rises and faster promotion.
Soldiers broke into Bouake's main weapons depot, arming themselves with rocket-launchers and other weapons mounted on pickup trucks, a military source said.
AFP's correspondent in the city said troops there had attacked all seven police posts, manned strategic junctions and put up barricades in the town centre.
A police source said the soldiers arrived at one police station at about 3:00 am (0300 GMT) and took away their Kalashnikov assault rifles.
The police headquarters in the city was also attacked, the source said.
All businesses and schools were closed in Bouake, which became the capital of a rebellion after former president Laurent Gbagbo stayed in power after a foiled 2002 coup attempt.
The effective partitioning of the country between a rebel-held north and a loyalist south sparked a decade of clashes and crises.
Rebel forces generally backed current President Alassane Ouattara, who took office in April 2011 after a bloody post-electoral showdown which ended when Gbagbo was arrested.
Gbagbo was turned over to the International Criminal Court in The Hague, where his trial began in January last year for crimes against humanity.
"I was really scared. I thought that they were going to come into my station to take petrol for free as they do regularly," Koffi Raphael, who runs a gas station not far from the barracks, told AFP.
In Daloa, "soldiers on motorbikes are driving around town shooting into the air," one resident had told AFP earlier.
"There's gunfire, we're scared, hiding out at home," another had said.
In November 2014, a strike by former rebels who had joined the army brought the country to a standstill after spreading to Abidjan from Bouake.
The nearly 9,000 strikers, who joined the army between 2009 and 2011, were demanding full payment of back pay and promotions.