By James Copnall
BBC correspondent in Abidjan
Tensions have been rising since a disarmament deadline was missed
In Ivory Coast, air raids carried out by government forces on the former rebels, known as the New Forces, seem to confirm the war has started again, despite the UN-backed peace process.
The raids come a week after the New Forces announced a state of maximum alert, and three weeks after a missed deadline for disarmament to begin.
For them, a ceasefire signed in July last year now seems to be little more than another worthless piece of paper fluttering down onto the pile of such documents that has built up in the country since the crisis began on 19 September 2002.
The bombs bursting on New Forces' town of Bouake have caused real damage in the rebel-controlled north, and heighten huge tensions in the government-held south.
Medecins Sans Frontieres says they have treated at least 39 people for serious injuries in Bouake's hospital, and there are likely to be many injured in Korhogo, following the bombardment there on Thursday.
New Forces leader Guillaume Soro expressed his amazement at the attacks, and claimed they had left at least three people dead.
Coulibaly Zie, who lives in Korhogo, says the raid on his town, situated near the northern border with Mali and Burkina Faso, has created a wave of panic.
"As soon as the planes flew over, everyone started screaming," he told the BBC.
"We saw the flashes as they dropped their bombs. It was terrifying."
New Forces representative Issa Doumbia says the attacks have left the north in a state of disorder.
"They cut the electricity so we cannot see anything," he explained.
"The [mobile] phones are out, so it is very difficult to know what is going on. But we are preparing to defend ourselves."
The man charged with fighting off the aerial invasions is Sergeant Dramane Soro, known as Sergeant Docteur.
When I travelled to Bouake earlier this week, he boasted to me about his men's anti-aircraft capabilities.
"We'll be ready for the attack when it comes, just you see," he said.
Yet, despite their preparations, the New Forces have manifestly been unable to deal with the raids by the army's two Sukhoi 25 fighter-bombers.
In the main city in the government-held south, Abidjan, reactions to the attacks have been very mixed.
The Young Patriots, the pro-President Laurent Gbagbo organisation, were delighted by the government offensive.
The Young Patriots are delighted by the government offensive
On Thursday, groups of Young Patriots demonstrated at what appeared to be carefully chosen locations.
The opposition newspapers Le Patriote and 24 Heures had their buildings destroyed, allegedly by the organisation, accused by the UN of being a militia.
Opposition party buildings have also been burnt and looted and the UN and French military, who stand between the belligerent factions, were targets of abuse.
Young Patriots leader Charles Ble Goude called on his men to remain focused.
"Our enemy is the rebels, no-one else," he said.
Security Minister Martin Bleou has called for calm.
Yet in Thursday's televised evening news, there was no mention of the aerial attacks on the north.
International radio stations - including the BBC - have been off the air since Thursday morning, which means many people are still unsure if the rumours they have heard are true.
Newspapers accused of colluding with the New Forces were attacked
"People have said lots of things, but I heard nothing on the news, so I am not sure," one taxi driver told me.
Most people in Abidjan seem devastated - if not surprised - that fighting has broken out again in what was once the region's most stable country.
The streets of the central business district, the Plateau, emptied early and quickly, as people fled to the safety of home.
The army have said there are no immediate plans for a ground attack, despite a small skirmish with rebel forces.
They are waiting for a response from the impartial forces, the UN and French, who have more than 10,000 peacekeepers in the country.
The UN has no mandate to stop planes
Why have they not acted to stop an offensive in a country stumbling on the brink of the abyss?
French military spokesman Colonel Henri Aussavy told the BBC he has the military capacity to stop the aerial assaults.
But the French troops come under the command of the UN, which has not given them the mandate to attempt to stop the planes.
Until the UN decides to act, it is difficult to see what will stop the trickle of Thursday's attacks turning into the torrent of combat.